Physical Things and Their Existence: The Real Difference Between Mind and Body

It now remains that I examine whether any Corporeal Beings do Exist; And already I know that (as they are the Object of Pure Mathematicks) they May (at least) Exist, for I clearly and distinctly perceive them; and doubtless God is able to make, whatever I am able to perceive, and I never Judged any thing to be beyond his Power, but what was Repugnant to a distinct perception. Moreover, such Material Beings seem to Exist from the faculty of Imagination, which I find my self make use of, when I am conversant about them: for if I attentively Consider what Imagination is, ’twill appear to be only a certain Application of our Cognoscitive or knowing Faculty to a Body or Object that is before it; and if it be before it, It must Exist.

I must now examine whether any bodily beings exist. I already know that, as the objects of pure mathematics, they may at least exist. For I perceive them clearly and distinctly. And surely God is able to make whatever I am able to perceive. I have never judged anything beyond his power unless it contradicted a distinct perception. Moreover, such material beings seem to exist because of the faculty of imagination. I find myself using this faculty when I consider material beings. For if I carefully consider what imagination is, it appears to be nothing more than this: a particular application of our faculty of knowing to a body or object present to that faculty. And if the body or object is present to that faculty, the body or object must exist.

But that this may be made more Plain, I must first examine the difference between Imagination, and pure Intellection, or Understanding. So, for example, when I Imagine a Triangle, I do not only Understand that it is a figure comprehended by three Lines, but I also behold with the eye of my mind those three lines as it were before Me, and this is that which I call imagination. But if I convert my Thoughts to a Chiliogone, or Figure consisting of a Thousand Angles, I know as well that this Is a figure comprehended by a Thousand sides, as I know that a Triangle is a Figure Consisting of three sides; but I do not in the same Manner Imagine, or behold as present those thousand sides, as I do the three sides of a Triangle. And tho at the time when I so think of a Chiliogone, I may confusedly represent to my self some Figure (because whenever I Think of a Corporeal Object, I am used to Imagine some Shape or other) yet ’tis evident that this Representation is not a Chiliogone, because ’tis in nothing different from what I should Represent to my self if I thought of a Milion-angled figure, or any other Figure of More sides; Neither does such a Confused Representation help me in the least to know those Properties, by which a Chiliogone differs from other Polygones or Manyangled Figures. But if a Question be put concerning a Pentagone, I know I may Understand its Shape, as I Understand the Shape, of a Chiliogone, without the help of Imagination, but I can also imagine it, by applying the Eye of my Mind to its Five sides, and to the Area or space contained by Them; And herein I manifestly perceive that there is required a peculiar sort of Operation in the Mind to imagine a Thing, which I require not to Understand a Thing; which New Operation of the Mind plainly shews the difference between imagination and pure Intellection.

But to make this more clear, I must first examine the difference between imagination and pure thought, or understanding. For example, when I imagine a triangle, I not only understand that it is a figure enclosed by three lines. I also see those three lines with my mind’s eye, as though they were in front of me. This is what I call imagination. But if I turn my thoughts to a chiliogon, or a figure with a thousand angles, I understand its definition equally well. I know it is a figure enclosed by a thousand sides. I know this just as well as I know that a triangle is a figure with three sides. But I do not imagine, or see as present, those thousand sides as I do a triangle’s three sides. And although I may form a vague image of some figure when I think of a chiliogon, that image is inadequate. Whenever I think of a physical object, I am used to imagining some shape or other. Yet this image is clearly not a chiliogon. It is no different from the image I would form when thinking of a million-angled figure. Nor would it differ if I thought of any other figure with more sides. Nor does such a vague image help me at all to know the properties that distinguish a chiliogon. Those properties distinguish it from other polygons, or many-angled figures. But if I am asked about a pentagon, I know I can understand its shape without the help of imagination. I can do so just as I understand the shape of a chiliogon. But I can also imagine a pentagon by focusing my mind’s eye on its five sides. I can also focus on the area, or space, enclosed by them. Here I clearly see that imagining something requires a particular kind of mental activity that understanding something does not require. This additional mental activity clearly shows the difference between imagination and pure thought.

Besides this, I Consider that this Power of Imagination which is in me (as it differs from the Power of Understanding) does not appertain to the Essence of Me, that is, of my mind, for tho I wanted it, yet certainly I should be the same He, that now I am: from whence it seems to follow, that it depends on something different from my self; and I easily perceive that if any Body whatever did Exist, to which my Mind were so conjoyn’d, that it may Apply it self when it pleased to Consider, or (as it were) Look into this Body; From hence, I say, I perceive It may so be, that by this very Body I may Imagine Corporeal Beings: So that this Manner of Thinking differs from pure Intellection only in this, that the Mind, when it Understands, does as it were turn it self, to it self, or Reflect on it self, and beholds some or other of those Ideas which are in it self; But when it Imagines, it Converts it self upon Body, and therein beholds something Conformable to that Idea, which it hath understood, or perceived by Sense.

Besides this, I consider the power of imagination within me, as distinct from the power of understanding. It does not belong to the essence of me, that is, of my mind. For even if I lacked imagination, I would certainly be the same person that I am now. From this, it seems to follow that imagination depends on something different from myself. And I easily see how this could work if any body at all existed to which my mind was joined. My mind could then turn to consider this body whenever it pleased, or, as it were, look into this body. From this, I say, I see that it may be through this very body that I imagine bodily things. So this way of thinking differs from pure understanding only in the following respect. When the mind understands, it turns, as it were, toward itself, or reflects on itself. It looks at one or another of the ideas within itself. But when the mind imagines, it turns toward a body. There it sees something corresponding to the idea it has understood or perceived through the senses.

But ’tis to be remembred, that I said, I easily conceive Imagination May be so performed, supposing Body to Exist. And because no so convenient manner of Explaining it offers it self, from thence I probably guess, that Body does Exist. But this I only say probably, for tho I should accurately search into all the Arguments drawn from the distinct Idea of Body, which I find in my Imagination, yet I find none of them, from whence I may necessarily conclude, that Body does Exist.

But remember what I said: I can easily understand how imagination may be carried out this way, assuming body does exist. And because no equally suitable explanation comes to mind, I infer that body does exist, though only probably. But I say only probably. Even if I carefully examine all the arguments drawn from the distinct idea of body in my imagination, none suffice. None allow me to necessarily conclude that body does exist.

But I have been accustomed to Imagine many other things besides that Corporeal Nature which is the Object of pure Mathematicks; such as are, Colours, Sounds, Tasts, Pain, &c. but none of these so distinctly. And because I perceive these better by Sense, from Which by the Help of the Memory they come to the Imagination, that I may with the Greater advantage treat of them, I ought at the same time to Consider Sence, and to try whether from what I perceive by that way of Thought, which I call Sense, I can deduce any certain Argument for the Existence of Corporeal Beings.

But I am used to imagining many things besides the bodily nature that is the subject of pure mathematics. These include colors, sounds, tastes, pain, and so on, but I imagine none of these as clearly. And I perceive these things better through sense. These perceptions reach the imagination through the senses with the help of memory. So, to examine these things more effectively, I should also consider sense. I should try to determine whether the perceptions supplied by the kind of thought I call sense offer any certain proof of the existence of bodily things.

And first I will here reflect with my self, what those things were, which being perceived by Sence I have heretofore thought True, and the Reasons why I so thought: I will then enquire into the Reasons for which I afterwards doubted those things. And last of all I will consider what I ought to think of those Things at Present.

First, I will reflect on what I once believed was true based on my senses. I will consider the reasons why I thought so. Then I will examine the reasons why I later doubted those things. Finally, I will consider what I ought to think about those things now.

First therefore I have always thought that I have had an Head, Hands, Feet, and other Members, of which This Body (which I have look’d upon as a Part of Me, or Perhaps as my Whole self) Consists; And I have also thought that this Body of Mine is Conversant or engaged among many Other Bodies, by which it is Liable to be affected with what is advantagious or hurtful; What was Advantagious I judged by a certain sense of Pleasure, what was Hurtful by a sense of Pain. Furthermore, besides Pleasure and Pain, I perceived in my self Hunger, Thirst, and other such like Appetites, as also certain Corporeal Propensions to Mirth, Sadness, Anger, and other like Passions.

First, then, I have always thought I had a head, hands, feet, and other limbs making up this body. (I regarded this body as a part of me, or perhaps as my whole self.) I also thought that this body of mine interacted with many other bodies. These other bodies could affect my body in helpful or harmful ways. I judged what was helpful by a certain feeling of pleasure, and what was harmful by a feeling of pain. Furthermore, besides pleasure and pain, I felt hunger, thirst, and other similar appetites within myself. I also felt certain bodily inclinations toward joy, sadness, anger, and other similar emotions.

As to What hapned to me from Bodies without, Besides the Extension, Figure, and Motion of those Bodies, I also perceived in them Hardness, Heat, and other tactile Qualities, as also Light, Colours, Smells, Tasts, Sounds, &c. and by the Variation of these I distinguish’d the Heaven, Earth, and Seas, and all other Bodies from each other.

As for my experiences of external bodies, I perceived more than the spatial extent, shape, and motion of those bodies. I also perceived hardness, heat, and other qualities felt by touch. I perceived light, colours, smells, tastes, sounds, and so on. Through differences in these qualities, I distinguished the sky, earth, and seas, and all other bodies from one another.

Neither was it wholly without Reason (upon the account of these Ideas of Qualities, which offer’d themselves to my Thoughts, and which alone I properly and Immediately perceived) that I thought my self to Perceive some Things Different from my Thought, viz. The Bodies or Objects from whence these Ideas might Proceed; for I often found these Ideas come upon me without my Consent or Will; so that I can neither perceive an Object (tho I had a mind to it) unless it were before the Organs of my Sense; Neither can I Hinder my self from perceiving it, when it is Present.

Nor was I entirely without reason to believe I perceived some things different from my thought. My reason lay in these ideas of qualities that came into my mind. These alone were what I truly and directly perceived. The other things were the bodies or objects from which these ideas might come. For I often found these ideas coming to me without my consent or will. So I cannot perceive an object (even if I want to) unless the object is before my sense organs. Nor can I prevent myself from perceiving the object when the object is present.

And seeing that those Ideas which I take in by sense are much more Lively, Apparent and in their kind more distinct, than any of those which I knowingly and Willingly frame by Meditation, or stir up in my Memory; it seems to me that they cannot proceed from my self. There remains therefore no other way for them to come upon me, but from some other Things Without Me. Of Which Things seeing I have no other Knowledge but from these Ideas, I cannot Think but that these Ideas are like the Things.

The ideas I receive through my senses are much more vivid, clear, and, in their own way, more distinct than any ideas I consciously and willingly form through reflection or call up in my memory. So these sensory ideas seem unable to come from myself. The only remaining possibility is that these ideas come to me from other things outside me. Since I know those things only through these ideas, I cannot help thinking that these ideas are like those things.

Moreover, Because I remember that I first made use of my senses before my Reason; and because I did perceive that those Ideas which I my self did frame were not so Manifest as those which I received by my senses, but very often made up of their parts, I was easily perswaded to think that I had no Idea in my Understanding, which I had not First in my sense.

Moreover, I remember that I first used my senses before my reason. I also noticed that the ideas I formed myself were not as clear as those I received through my senses. Instead, they were very often made up of parts of those sensory ideas. For these reasons, I was easily persuaded that I had no idea in my understanding that had not first come through my senses.

Neither was it without Reason that I Judged, That Body (which by a peculiar right I call my Own) to be more nighly appertaining to Me then any other Body. For from It, as from other Bodies, I can never be seperated, I was sensible of all Appetites and Affections in It and for It, and lastly I perceived pleasure and Pain in its Parts, and not in any other Without it. But why from the sense of Pain a certain Grief, and from the sense of pleasure a certain Joy of the Mind should arise, or Why that Gnawing of the stomach, Which I call Hunger, should put me in mind of Eating, or the driness of my Throat of Drinking, I can give no other Reason but that I am taught so by Nature. For to my thinking there is no Affinity or Likeness between that Gnawing of the Stomach, and the desire of Eating, or between the sense of Pain, and the sorrowful thought from thence arising. But in this as in all other judgments that I made of sensible objects, I seem’d to be taught by Nature, for I first perswaded my self that things were so or so, before ever I enquired into a Reason that may prove it.

Nor was I wrong to judge that body (which I call my own by a special right) as belonging more closely to me than any other body. For I could never be separated from it as I could from other bodies. I felt all my appetites and emotions in it and for it. Finally, I felt pleasure and pain in its parts, and not in anything outside it. But why should the feeling of pain cause a certain sadness in the mind? And why should the feeling of pleasure cause a certain joy of the mind? Why should the gnawing in my stomach, which I call hunger, make me think of eating? Or why should the dryness of my throat make me think of drinking? I can give no reason except that nature teaches me these connections. For I see no connection or resemblance between the gnawing in my stomach and the desire for food. Nor do I see any between the feeling of pain and the sad thought that arises from it. But in these judgments, as in all my other judgments about things perceived through the senses, nature seemed to teach me. For I convinced myself that things were one way or another before I ever looked for a reason to prove it.

But afterwards I discover’d many experiments, wherein my senses so grosly deceived me, that I would never trust them again; for Towers which seem’d Round a far off, nigh at hand appear’d square, and large Statues on their tops seem’d small to those that stood on the ground; and in numberless other things, I perceived the judgements of my outward senses were deceived: and not of my outward only, but of my inward senses also; for what is more intimate or inward than Pain? And yet I have heard from those, whose Arm or Leg was cut off, that they have felt pain in that part which they wanted, and therefore I am not absolutely certain that any part of me is affected with pain, tho I feel pain therein. To these I have lately added two very general Reasons of doubt; The first was, that while I was awake, I could not believe my self to perceive any thing, which I could not think my self sometimes to perceive, tho I were a sleep; And seeing I cannot believe, that what I seem to perceive in my sleep proceeds from outward Objects, what greater Reason have I to think so of what I perceive whilst I am awake? The other Cause of Doubt was, that seeing I know not the Author of my Being (or at least I then supposed my self not to know him) what reason is there but that I may be so ordered by Nature as to be deceived even in those things which appear’d to me most true. And as to the Reasons, which induced me to give credit to sensible Things, ’twas easie to return an answer thereto, for finding by experience, that I was impelled by Nature to many Things, which Reason disswaded me from, I thought I should not far trust what I was taught by Nature. And tho the perceptions of my senses depended not on my Will, I thought I should not therefore conclude, that they proceeded from Objects different from my self; for perhaps there may be some other Faculty in me (tho as yet unknown to me) which might frame those perceptions.

But later I had many experiences in which my senses deceived me so badly that I would never trust them again. Towers that seemed round from far away appeared square up close. And large statues on top of those towers seemed small to people standing on the ground. In countless other cases, I found that the judgments of my external senses were mistaken. This was true not only of my external senses, but also of my internal senses. For what is more intimate or internal than pain? Yet I have heard people whose arms or legs were amputated say they felt pain in the missing part. So I am not absolutely certain that any part of my body is affected by pain, though I feel pain there. To these doubts I have recently added two very general reasons for doubt. The first was that, while awake, I could not believe I perceived anything I might not sometimes think I perceived while asleep. And I cannot believe that what I seem to perceive in my sleep comes from external objects. So what greater reason do I have to think that what I perceive while awake comes from external objects? The other reason for doubt was that I did not know the Author of my being. (Or at least, I then supposed that I did not know him.) So what reason did I have to rule out being so constituted by nature as to be deceived? This could apply even to things that appeared most true to me. As for the reasons that led me to believe in things perceived by the senses, answering them was easy. Experience showed me that nature drove me toward many things that reason warned me against. So I thought I should not put much trust in what nature taught me. And although my sensory perceptions did not depend on my will, I thought I should not draw a particular conclusion. Their independence did not mean they came from objects distinct from myself. For perhaps I have some other faculty (though still unknown to me) that might produce those perceptions.

But now that I begin better to know my self and the Author of my Original, I do not think, that all things, which I seem to have from my senses are rashly to be admitted, neither are all things so had, to be doubted. And first because I know that whatever I clearly and distinctly perceive, may be so made by God as I perceive them; the Power of understanding clearly and distinctly one Thing without the other is sufficient to make Me certain that One Thing is different from the Other; because it may at least be placed apart by God, and that it may be esteem’d different, it matters not by what Power it may be so sever’d. And therefore from the knowledge I have, that I my self exist, and because at the same time I understand that nothing else appertains to my Nature or Essence, but that I am a thinking Being, I rightly conclude, that my Essence consists in this alone, that I am a thinking Thing. And tho perhaps (or, as I shall shew presently, ’tis certain) I have a Body which is very nighly conjoyned to me, yet because on this side I have a clear and distinct Idea of my self, as I am only a thinking Thing, not extended; and on the other side because I have a distinct Idea of my Body, as it is onely an extended thing, not thinking, ’tis from hence certain, that I am really distinct from my Body, and that I can exist without it.

But now I am beginning to know myself and the Author of my existence better. I do not think everything I seem to receive through my senses should be hastily accepted. Nor should everything received this way be doubted. First, I know that God can make whatever I perceive clearly and distinctly just as I perceive it. The ability to understand clearly and distinctly one thing without another therefore makes me certain that they are different. For God may at least separate them. To consider them different, it does not matter what power may separate them. I know that I myself exist. At the same time, I understand that nothing belongs to my nature or essence except being a thinking being. I therefore rightly conclude that my essence consists only in being a thinking thing. And although perhaps I have a body very closely joined to me, I can distinguish myself from my body. (Or, as I will show shortly, having a body is certain.) On one hand, I have a clear and distinct idea of myself as only a thinking thing, without extension. On the other hand, I have a distinct idea of my body as only an extended thing, not thinking. Because of these distinct ideas, it is certain that I am really distinct from my body. I can therefore exist without my body.

Moreover I find in my self some Faculties endow’d with certain peculiar waies of thinking, such as the Faculty of Imagination, the Faculty of Perception or sense; without which I can conceive my whole self clearly and distinctly, but (changing the phrase) I cannot conceive those Faculties without conceiving My self, that is, an understanding substance in which they are; for none of them in their formal Conception includes understanding; from whence I perceive they are as different from me, as the modus or manner of a Thing is different from the Thing it self.

Moreover, I find in myself some faculties with certain distinctive ways of thinking. These include the faculty of imagination and the faculty of perception or sense. Without these faculties, I can conceive of my whole self clearly and distinctly. But, to put it another way, I cannot conceive of those faculties without conceiving of myself. That is, I must conceive of an understanding substance in which these faculties exist. For none of these faculties, in their formal definition, includes understanding. From this I see that these faculties are as different from me as a thing’s mode or manner of being is different from the thing itself.

I acknowledge also, that I have several other Faculties, such as changing of place, putting on various shapes, &c. Which can no more be understood without a substance in which they are, then the foremention’d Faculties, and consequently they can no more be understood to Exist without that substance: But yet ’tis Manifest, that this sort of Faculties, to the End they may exist, ought to be in a Corporeal, Extended, and not in an Understanding substance, because Extension, and not Intellection or Understanding is included in the Clear and Distinct conception of them.

I also acknowledge that I have several other capacities, such as changing my location, taking on various shapes, and so on. Like the capacities mentioned earlier, these cannot be understood without a substance in which they exist. Consequently, neither can they be understood to exist without that substance. But clearly, for these capacities to exist, they must belong to a bodily, extended substance, not a thinking substance. This is because extension, not thought or understanding, is included in the clear and distinct conception of these capacities.

But there is also in me a certain Passive Faculty of sense, or of Receiving and Knowing the Ideas of sensible Things; of which Faculty I can make no use, unless there were in my self, or in something else, a certain Active Faculty of Producing and Effecting those Ideas. But this cannot be in my self, for it Pre-supposes no Understanding, and those Ideas are Produced in me, tho I help not, and often against my Will. There remains therefore no Place for this Active Faculty, but that it should be in some substance different from me. In which because all the Reallity, which is contain’d Objectively in the Ideas Produced by that Faculty, ought to be contain’d Formally or Eminently (as I have Formerly taken notice) this substance must be either a Body (in which what is in the Ideas Objectively is contain’d Formally) or it Must Be God, or some Creature more excellent then a Body (In which what is in the Ideas Objectively is contain’d Eminently). But seeing that God is not a Deceivour, ’tis altogether Manifest, that he does not Place these Ideas in me either Immediately from himself, or Mediately from any other Creature, wherein their Objective Reallity is not * contain’d Formally, but only Eminently. And seeing God has given me no Faculty to discern Whether these Ideas proceed from Corporeal or Incorporeal Beings, but rather a strong Inclination to believe that they are sent from Corporeal Beings, there is no Reason Why God should not be counted a Deceiver, if these Ideas came from any Where, but from Corporeal Things. Therefore we must conclude that there are Corporeal Beings. Which perhaps are not all the same as I comprehend them by my sense (for Perception by sense is in many Things very Obscure and Confused) but those things at least, which I clearly and distinctly Understand, that is to say, all those things which are comprehended under the Object of Pure Mathematicks; those things I say at least are True.

But I also have a certain passive capacity for sensation, or for receiving and knowing the ideas of things perceived through the senses. I cannot use this capacity unless there is a certain active capacity in me or in something else. This active capacity must produce and bring about those ideas. But this capacity cannot be in me, since it requires no understanding. Those ideas arise in me without my help, and often against my will. Therefore, this active capacity can only exist in some substance different from me. All the reality contained objectively in the ideas produced by that capacity must exist formally or eminently in this substance. (I have already noted this.) So this substance must be either a body, God, or some creature more excellent than a body. In a body, what exists objectively in the ideas exists formally. In God or such a creature, what exists objectively in the ideas exists eminently. But since God is not a deceiver, the following is entirely clear. He does not place these ideas in me either directly himself or indirectly through another creature of a certain kind. Such a creature would be one in which their objective reality is not * contained formally, but only eminently. And God has given me no capacity to tell whether these ideas come from bodily or nonbodily beings. Instead, he has given me a strong inclination to believe that they come from bodily beings. So there would be no reason not to call God a deceiver if these ideas came from anywhere else. Therefore, we must conclude that bodily beings exist. Perhaps these beings are not entirely as I perceive them through my senses. (Sense perception is very obscure and confused in many respects.) But at least the things I understand clearly and distinctly are true. That is, at least everything included in the subject matter of pure mathematics is true.

As to What Remains, They are either some Particulars, as that the Sun is of such a Bigness or Shape, &c. or they are Things less Clearly Understood, as Light, Sound, Pain, &c. And tho these and such like Things may be very Doubtful and Uncertain, yet because God is not a Deceiver, and because that (Therefore) none of my Opinions can be false unless God has Given me some Faculty or other to Correct my Error, hence ’tis that I am incouraged with the Hopes of attaining Truth even in these very Things.

As for what remains, these are either specific details, such as the Sun’s size or shape, etc. Or they are things less clearly understood, such as light, sound, pain, etc. And although these and similar things may be very doubtful and uncertain, God is not a deceiver. Because of this, none of my opinions can be false unless God has given me some ability to correct my error. This encourages me to hope that I can reach the truth even about these very things.

And certainly it cannot be doubted but whatever I am taught by Nature has something therein of Truth. By Nature in General I understand either God himself, or the Coordination of Creatures Made by God. By my Own Nature in Particular I understand the Complexion or Association of all those things which are given me by God.

And there is certainly no doubt that whatever I learn from Nature contains some Truth. By Nature in general, I mean either God himself or the order of beings created by God. My Own Nature in particular means the makeup or combination of all God has given me.

Now there is nothing that this my Nature teaches me more expresly then that I have a Body, Which is not Well when I feel Pain, that this Body wants Meat or Drink When I am Hungry or Dry, &c. And therefore I ought not to Doubt but that these things are True. And by this sense of Pain, Hunger, Thirst, &c. My Nature tells me that I am not in my Body, as a Mariner is in his Ship, but that I am most nighly conjoyn’d thereto, and as it were Blended therewith; so that I with It make up one thing; For Otherwise, when the Body were hurt, I, who am only a Thinking Thing, should not therefore feel Pain, but should only perceive the Hurt with the Eye of my Understanding (as a Mariner perceives by his sight whatever is broken in his Ship) and when the Body wants either Meat or Drink, I should only Understand this want, but should not have the Confused sense of Hunger or Thirst; I call them Confused, for certainly the Sense of Thirst, Hunger, Pain, &c. are only Confused Modes or Manners of Thought arising from the Union and (as it were) mixture of the Mind and Body.

Now nothing in my nature teaches me more clearly than that I have a body. My body is not well when I feel pain. My body needs food or drink when I am hungry or thirsty, and so on. So I should not doubt that these things are true. Through these sensations of pain, hunger, thirst, and so on, my nature tells me something more. I am not in my body as a sailor is in his ship. Instead, I am very closely joined to my body and, as it were, blended with it. Thus I and my body make up one thing. For otherwise, if my body were injured, I, being only a thinking thing, would not feel pain. Instead, I would only perceive the injury through the eye of my understanding. This would be like a sailor seeing whatever is broken in his ship. And when my body needed food or drink, I would only understand that need. But I would not have the confused sensation of hunger or thirst. I call these sensations confused because the sensations of thirst, hunger, pain, and so on certainly are only confused forms or ways of thinking. These arise from the union and, as it were, mixture of the mind and body.

I am taught also by Nature, that there are many other Bodies Without and About my Body, some whereof are to be desired, others are to be Avoided. And because that I Perceive very Different Colours, Sounds, Smells, Tasts, Heat, Hardness, and the Like, from thence I Rightly conclude that there are Correspondent Differences in Bodies, from which these different perceptions of sense proceed, tho perhaps not Alike. And because that some of these perceptions are Pleasant, others Unpleasant, ’tis evidently certain, that my Body, or rather my Whole self (as I am compounded of a Mind and Body) am liable to be Affected by these Bodies which encompass me about.

Nature also teaches me that many other bodies exist outside and around my body. Some are to be desired, others avoided. I perceive very different colors, sounds, smells, tastes, heat, hardness, and similar qualities. From these perceptions, I rightly conclude that there are corresponding differences in bodies. These different sensory perceptions arise from those differences, though perhaps the perceptions do not resemble them. And because some of these perceptions are pleasant and others unpleasant, one thing is evidently certain. My body, or rather my whole self, can be affected by the bodies surrounding me. This is because I am made up of a mind and a body.

There are many Other Things Also which Nature seems to teach Me, but Really I am not taught by It, but have gotten them by an ill use of Passing my Judgement Inconsiderately, and from hence it is that these things happen often to be false; as that all space is Empty, in which I find nothing that works upon my Senses; That in a hot Body there is something like the Idea of Heat which is in me; That in a White or Green Body there is the same Whiteness or Greenness which I perceive; And the same Taste in a bitter or sweet Thing, &c. That Stars, Castles, and Other Remote Bodies are of the same Bigness and Shape, as they are Represented to my senses: and such like. But that I may not admit of any Thing in this very matter, which I cannot Distinctly perceive, it behoves me here to determine more Accurately What I mean when I say, That I am taught a Thing by Nature.

There are many other things that nature seems to teach me. But in reality, nature does not teach me these things. Instead, I have acquired these beliefs by misusing my judgment and judging without careful thought. As a result, these beliefs often turn out to be false. For example, I believe that all space is empty wherever I find nothing that affects my senses. I believe that a hot body contains something like the idea of heat within me. I believe that a white or green body contains the same whiteness or greenness that I perceive. And I believe that a bitter or sweet thing contains the same taste I experience, and so on. I believe that stars, castles, and other distant bodies have the same size and shape as represented to my senses. And I hold other beliefs like these. But I must not accept anything about this subject that I cannot clearly perceive. For that purpose, I must define more precisely what I mean when I say, I am taught something by nature.

Here I take Nature more strictly, then for the Complication of all those Things which are Given me by God; For in this Complication there are many things contain’d which relate to the Mind alone, as, That I perceive What is done cannot be not Done, and all Other things which are known by the Light of Nature, but of these I speak not at present. There are also many Other Things which belong only to the Body, as, That it tends Downwards and such like, of these also I treat not at Present. But I speak of those Things only which God hath bestowed upon me as I am Compounded of a Mind and Body together, and not differently Consider’d. ’Tis Nature therefore thus taken that teaches me to avoid troublesome Objects, and seek after pleasing Ones; but it appears not that this Nature teaches us to conclude any thing of these Perceptions of our senses, before that we make by our Understanding a diligent examination of outward Objects; for to Enquire into the Truth of Things belongs not to the Whole Compositum of a Man as he Consists of Mind and Body, but to the Mind alone.

Here I use Nature more narrowly than to mean the whole collection of Things God has Given me. For this collection includes many things relating to the Mind alone. For example, I perceive that What is done cannot be undone. It also includes all Other things known by the Light of Nature, but I am not discussing these now. There are also many Other Things belonging only to the Body, such as its tendency to move Downwards. I am not discussing these now either. Instead, I speak only of Things God has given me as a union of Mind and Body together. I am not considering mind and body separately. Understood this way, Nature teaches me to avoid unpleasant Objects and seek pleasant Ones. But this Nature does not appear to teach us to draw conclusions from our sensory Perceptions without further examination. First, we must use our Understanding to examine external Objects carefully. For discovering the Truth about Things is not the task of the Whole Person consisting of Mind and Body. That task belongs to the Mind alone.

So that tho a star affect my eye no more then a small spark of Fire, yet there is in my Eye no Real or Positive Inclination to believe One no bigger then the Other, but thus I have been used to Judge from my Childhood without any Reason: and tho coming nigh the Fire I feel Heat, and Coming too nigh I feel Pain, yet there is no Reason to perswade me, That in the Fire there is any thing like either that Heat or that Pain, but only that there is something therein, Whatever it be, that excites in us those sensations of Heat or Pain: and so tho in some space there may be nothing that Works on my senses, it does not from thence follow, that there is no Body there; for I see that in these and many other things I am used to overturn the Order of Nature, because I use these perceptions of sense (which properly are given me by Nature to make known to the mind what is advantagious or hurtful to the Compositum, whereof the mind is part, and so far only they are Clear and Distinct enough) as certain Rules immediately to discover the Essence of External Bodies, of Which they make known nothing but very Obscurely and Confusedly.

So although a star affects my eye no more than a small spark of fire, my eye has no real or positive tendency to believe that one is no bigger than the other. Rather, I have been used to judging this way since childhood, without any reason. And although I feel heat when approaching a fire, and pain when I come too close, neither sensation gives me reason to believe that the fire contains anything like that heat or pain. There is only reason to believe that something in the fire, whatever it is, causes those sensations of heat or pain. Likewise, although some space may contain nothing that acts on my senses, it does not follow that no body exists there. For I see that in these and many other matters, I habitually reverse the order of nature. I use these sense perceptions as reliable rules for directly discovering the essential nature of external bodies. But nature gives me these perceptions to tell my mind what benefits or harms the composite whole of which the mind is part. Only for that purpose are these perceptions clear and distinct enough. They reveal the essential nature of external bodies only very obscurely and confusedly.

I have * formerly shewn how my Judgement happens to be false notwithstanding Gods Goodness. But now there arises a new Difficulty concerning those very things which Nature tells me I am to prosecute or avoid, concerning my Internal senses, Wherein I find many Errors, as when a Man being deceived by the Pleasant Taste of some sort of Meat, devours therein some hidden Poyson. But in this very Instance it cannot be said, that the Man is impelled by Nature to desire the Poyson, for of that he is wholly Ignorant; but he is said to Desire the Meat only as being of a grateful Taste; and from hence nothing can be concluded but, That Mans-Nature is not All-knowing; which is no Wonder seeing Man is a Finite Being, and therefore nothing but Finite Perfections belong to him.

I have * already shown how my judgment can be false despite God’s goodness. But now a new difficulty arises about the things nature tells me to pursue or avoid. This difficulty concerns my internal senses, in which I find many errors. For example, a man may be misled by the pleasant taste of some food and swallow poison hidden in it. But in this example, we cannot say that nature drives the man to desire the poison. He knows nothing about the poison. Rather, he desires the food only because it tastes pleasant. So we can conclude only that human nature is not all-knowing. This limitation is no surprise, since man is a finite being, and therefore only finite perfections belong to him.

But We often err even in those things to Which we are Impelled by Nature, as when sick men desire that Meat or Drink, which will certainly prove Hurtful to them. To this it may perhaps be reply’d, That they Err in this because their Nature is Corrupt. But this Answers not the Difficulty, For a sick man is no less Gods Creature then a Man in Health, and therefore ’tis as Absurd to Imagine a Deceitful Nature imposed by God on the One as on the Other; And as a Clock that is made up of Wheels and Weights does no less strictly observe the Laws of its Nature, when it is ill contrived, and tells the hours falsly, as when it answers the Desire of the Artificer in all performances; so if I consider the body of a Man as a meer Machine or Movement, made up and compounded of Bones, Nerves, Muscles, Veins, Blood, and Skin; so that, tho there were no mind in It, yet It would perform all those Motions which now are in it (those only excepted which Proceed from the Will, and consequently from the Mind) I do easily acknowledge, that it would be as natural for him (if for example sake he were sick of a Dropsie) to suffer that Driness of his Throat which uses to bring into his mind the sense of Thirst, & that thereby his Nerves and other Parts would be so disposed as to take Drink, by Which his disease would be encreased; As (supposing him to be troubled with no such Distemper) by the like Driness of Throat he would be disposed to Drink, when ’tis Requisite. And tho, if I respect the Intended use of a Clock I may say that it Errs from its Nature, when it tells the Hours wrong, and so considering the Movement of a Mans Body as contrived for such Motions as are used to be performed thereby, I may think That also to Err from its Nature, if its Throat is Dry, when it has no want of Drink for its Preservation. Yet I Plainly discover, that this last Acceptation of Nature differs much from that whereof we have been speaking all this While, for this is only a Denomination extrinsick to the Things whereof ’tis spoken, and depending on my Thought, while it Compares a sick man, and a disorderly Clock with the Idea of an healthy man and a Rectified Clock. But by Nature in its former Acceptation I Understand something that is Really in the Things themselves, which therefore has something of Truth in it.

But we often go wrong even in things we are driven to do by nature. For example, sick people may desire food or drink that will certainly harm them. Perhaps someone may reply that they go wrong because their nature is corrupted. But this does not answer the difficulty. A sick person is no less God’s creature than a healthy person. So imagining that God gives either person a deceptive nature is equally absurd. A clock made of wheels and weights follows the laws of its nature just as strictly when poorly designed. The clock follows those laws when it tells the time incorrectly, just as when everything works as its maker intended. Similarly, I can consider the human body as a mere machine or mechanism. The body is made up of bones, nerves, muscles, veins, blood, and skin. Even without a mind, such a body would still perform all the movements it now performs. The only exceptions would be movements arising from the will, and therefore from the mind. Consider, for example, a person suffering from dropsy, a disease involving fluid buildup. I readily acknowledge that a dry throat would be just as natural for this person. Such dryness usually brings the sensation of thirst into the person’s mind. The dryness would prepare the person’s nerves and other parts to take a drink, worsening the disease. This response would be just as natural as the response in someone without that illness. In the healthy person, similar throat dryness would prompt drinking when drinking is needed. Still, if I consider a clock’s intended use, I may say the clock departs from its nature when it tells the time incorrectly. Likewise, I may consider the mechanism of a human body as designed for the movements it usually performs. I may then think the body also departs from its nature if its throat is dry when no drink is needed for its survival. Yet I clearly see that this last meaning of nature differs greatly from the meaning discussed until now. This last meaning is merely a label applied from outside to the things described. The label depends on my thought, as my thought compares a sick person and a faulty clock with an idea. That idea is of a healthy person and a properly adjusted clock. But by nature in its earlier meaning, I understand something actually present in the things themselves. This nature therefore contains something of truth.

But tho Respecting only a Body sick of a Dropsie it be an Extrinsick Denomination to say, that its Nature is Corrupt, because it has a Dry Throat, and stands in no need of Drink; yet respecting the Whole Compound or Mind joyn’d to such a Body, ’tis not a meer Denomination, but a real Error of Nature for it to thirst when drink is hurtful to it. It remains therefore here to be inquired, how the Goodness of God suffers Nature so taken to be deceivable.

But when considering only a body suffering from dropsy, it is an external description to say its nature is corrupt. This is because the body has a dry throat but has no need to drink. Yet consider the whole combination of mind and body, or the mind joined to such a body. Here, thirst is not merely a description, but a real error of nature. This error occurs when the person feels thirst even though drink is harmful to them. So we must still ask how the goodness of God allows nature understood in this way to be subject to error.

First therefore I understand that a chief difference between my Mind and Body consists in this, That my Body is of its Nature divisible, but my Mind indivisible; for while I consider my Mind or my self, as I am only a thinking Thing, I can distinguish no parts in Me, but I perceive my self to be but one entire Thing; and tho the whole Mind seems to be united to the whole Body, yet a Foot, an Arm, or any other part of the Body being cut off, I do not therefore conceive any part of my Mind taken away; Neither can its Faculties of desiring, perceiving, understanding, &c. be called its Parts, for ’tis one and the same, mind, that desires, that perceives, that understands; Contrarily, I cannot think of any Corporeal or extended Being, which I cannot easily divide into Parts by my thought, and by this I understand it to be divisible. And this alone (if I had known it from no other Argument) is sufficient to inform me, that my mind is really distinct from my Body.

First, I understand that a chief difference between my mind and body is this: my body is by nature divisible, but my mind is indivisible. For when I consider my mind, or myself, solely as a thinking thing, I can distinguish no parts in myself. Instead, I perceive myself as one whole thing. And although the whole mind seems united to the whole body, losing a foot, an arm, or any other body part does not mean losing any part of my mind. Nor can the mind’s abilities to desire, perceive, understand, and so on be called its parts. For it is one and the same mind that desires, perceives, and understands. By contrast, I cannot think of any bodily being, or any being extended in space, that I cannot easily divide into parts in thought. From this, I understand that such a being is divisible. This difference alone is enough to show me that my mind is truly distinct from my body, even if I knew this from no other argument.

Nextly I find, that my mind is not immediately affected by all parts of my body, but only by the Brain, and perhaps only by one small part of it, That, to wit, wherein the common sense is said to reside; Which part, as often as it is disposed in the same manner, will represent to the mind the same thing, tho at the same time the other parts of the body may be differently order’d. And this is proved by numberless Experiments, which need not here be related.

Next, I find that my mind is not directly affected by all parts of my body, but only by the Brain. Perhaps only one small part of the brain affects the mind, where the common sense is said to reside. Whenever this part is in the same state, it presents the same thing to the mind. This holds even though the other parts of the body may be arranged differently at the same time. Countless experiments prove this, and there is no need to describe them here.

Moreover I discover that the nature of my body is such, that no part of it can be moved by an other remote part thereof, but it may also be moved in the same manner by some of the interjacent parts, tho the more remote part lay still and acted not; As for example in the Rope,

Moreover, I find that the nature of my body follows this rule: Whenever a part is moved by another, distant part, some intervening parts can also move the first part. They can do so in the same manner, though the more distant part remains still and does nothing. For example, consider a rope,

A⸺B⸺C⸺D

A, B, C, D

if its end D. were drawn, the end A. would be moved no otherwise, than if one of the intermediate parts B. or C. were drawn, and the end D. rest quiet. So when I feel pain in my Foot, the consideration of Physicks instructs me, that this is performed by the help of Nerves dispersed through the Foot, which from thence being continued like Ropes to the very Brain, whilst they are drawn in the Foot, they also draw the inward parts of the Brain to which they reach, and therein excite a certain motion, which is ordain’d by Nature to affect the mind with a sense of Pain, as being in the Foot. But because these Nerves must pass through the Shin, the Thighs, the Loins, the Back, the Neck, before they can reach the Brain from the Foot, it may so happen, that tho that part of them, which is in the Foot were not touch’d, but only some of their intermediate parts, yet the same motion, would be caused in the Brain, as when the Foot it self is ill affected, from whence ’twill necessarily follow, that the mind should perceive the same Pain. And thus may we think of any other Sense.

If end D were pulled, end A would move just as if an intermediate part, B or C, were pulled while D remained still. So when I feel pain in my Foot, physics teaches me that Nerves spread throughout the Foot produce this sensation. These nerves are continued like ropes from the Foot all the way to the Brain. When drawn in the Foot, the nerves also draw the inner parts of the Brain they reach. This pull produces a certain motion in the Brain. Nature has arranged for this motion to give the mind a sense of Pain located in the Foot. But these Nerves must pass through the Shin, Thighs, Loins, Back, and Neck before reaching the Brain from the Foot. So it may happen that that part of the nerves in the Foot remains untouched, while some intermediate parts are affected. Yet this could cause the same motion in the Brain as when the Foot itself is harmed. It would necessarily follow that the mind would perceive the same Pain. And we may think of any other Sense in the same way.

I understand lastly, that seeing each single motion perform’d in that part of the Brain, which immediately affects the mind, excites therein only one sort of sense, nothing could be contrived more conveniently in this case, than that, of all those Senses which it can cause, it should cause that which cheifly, and most frequently conduces to the conservation of an healthful Man; And experience witnesses, that to this very end all our senses are given us by Nature; and therefore nothing can be found therein, which does not abundantly testifie the Power and Goodness of God. Thus for Example, when the Nerves of the Feet are violently and more than ordinarily moved, that motion of them being propagated through the Medulla Spinalis of the Back to the inward parts of the Brain, there it signifies to the mind, that something or other is to be felt, and what is this but Pain, as if it were in the Foot, by which the Mind is excited to use its indeavours for removing the Cause, as being hurtful to the Foot. But the Nature of Man might have been so order’d by God, that That same motion in the Brain should represent to the mind any other thing, viz. either it self as ’tis in the Brain, or it self as it is in the Foot, or in any of the other forementioned intermediate parts, or lastly any other thing whatsoever; but none of these would have so much conduced to the Conservation of the Body. In the like manner when we want drink, from thence arises a certain dryness in the Throat, which moves the Nerves thereof, and by their means the inward parts of the Brain, and this motion affects the mind with the sense of thirst; because that in this case nothing is more requisite for us to know, then that we want drink for the Preservation of our Health. So of the Rest.

Finally, I understand that each individual movement in the part of the brain that directly affects the mind produces only one kind of sensation. So nothing could be better arranged than for that movement to produce the most useful of all possible sensations. That sensation should be the one that most effectively and most often helps preserve a healthy person. Experience shows that Nature gives us all our senses for this very purpose. Therefore, nothing in our senses fails to give ample evidence of the power and goodness of God. For example, suppose the nerves in the feet are disturbed violently and more than usual. Their movement travels through the Medulla Spinalis, or spinal cord, to the inner parts of the brain. There, the movement signals to the mind that something is to be felt. And what is this sensation but pain, felt as if it were in the foot? The pain prompts the mind to try to remove the cause, since that cause is harmful to the foot. But God could have arranged human nature differently. The same movement in the brain could have presented something else to the mind. For example, the mind could have perceived the movement itself in the brain, in the foot, or in any intermediate part mentioned earlier. Or the movement could have presented anything else at all. But none of these alternatives would have contributed as much to the preservation of the body. Likewise, when we need a drink, that need produces a certain dryness in the throat. This dryness moves the nerves in the throat, which in turn move the inner parts of the brain. This movement affects the mind with the sensation of thirst. For in this situation, nothing is more important for us to know than that we need a drink to preserve our health. The same applies to the rest of our sensations.

From all which ’tis manifest, that (notwithstanding the infinite Goodness of God) ’tis impossible but the Nature of Man as he consists of a mind and body should be deceivable. For if any cause should excite (not in the Foot but) in the Brain it self, or in any other part through which the Nerves are continued from the Foot to the Brain, that self same motion, which uses to arise from the Foot being troubled, the Pain would be felt as in the Foot, and the sense would be naturally deceived; for ’tis consonant to Reason (seeing that That same motion of the Brain alwayes represents to the mind that same sense, and it oftner proceeds from a cause hurtful to the Foot, than from any other) I say ’tis reasonable, that it should make known to the mind the Pain of the Foot, rather than of any other part. And so if a dryness of Throat arises (not as ’tis used from the necessity of drink for the conservation of the Body, but) from an unusual Cause, as it happens in a Dropsie, ’tis far better that it should then deceive us; then that it should alwayes deceive us when the Body is in Health, and so of the Rest.

All this makes one thing clear: despite God's infinite goodness, human nature must be capable of being deceived. This is true of a human being as a combination of mind and body. Suppose something produces the very same movement that normally occurs when the foot is injured. Suppose the movement begins not in the foot, but in the brain itself. Or suppose it begins somewhere along the nerves running from the foot to the brain. The pain would be felt in the foot, and the senses would naturally be deceived. Yet this agrees with reason. The same brain movement always presents the same sensation to the mind. And this movement more often comes from something harmful to the foot than from any other cause. So, I say, it is reasonable for the movement to tell the mind about pain in the foot. It should do this rather than indicate pain in any other part. Likewise, suppose dryness in the throat arises from an unusual cause, as happens in dropsy. Usually, such dryness comes from the need to drink to preserve the body. In this unusual case, it is far better for the dryness to deceive us then. The alternative would be for dryness to always deceive us when the body is healthy. The same applies to the other cases.

And this consideration helps me very much, not only to understand the Errors to which my Nature is subject, but also to correct and avoid them. For seeing I know that all my Senses do oftener inform me falsly than truely in those things which conduce to the Bodies advantage; and seeing I can use (almost alwayes) more of them than one to Examine the same thing, as also I can use memory, which joyns present and past things together, and my understanding also, which hath already discovered to me all the causes of my Errors, I ought no longer to fear, that what my Senses daily represent to me should be false. But especially those extravagant Doubts of my First Meditation are to be turn’d off as ridiculous; and perticularly the chief of them, viz. That * of not distinguishing Sleep from Waking, for now I plainly discover a great difference, between them, for my Dreams are never conjoyned by my memory with the other actions of my life, as whatever happens to me awake is; and certainly if (while I were awake) any person should suddenly appear to me, and presently disappear (as in Dreams) so that I could not tell from whence he came or where he went, I should rather esteem it a Spectre or Apparition feign’d in my Brain, then a true Man; but when such things occur, as I distinctly know from whence, where, and when they come, and I conjoyn the perception of them by my memory with the other Accidents of my life, I am certain they are represented to me waking and not asleep, neither ought I in the least to doubt of their Truth, if after I have called up all my senses, memory, and understanding to their Examination I find nothing in any of them, that clashes with other truths; For God not being a Deceiver, it follows, that In such things I am not deceived. But because the urgency of Action in the common occurrences of Affairs will not alwayes allow time for such an accurate examination, I must confess that Mans life is subject to many Errors about perticulars, so that the infirmity of our Nature must be acknowledged by Us.

And this consideration helps me greatly, not only to understand the errors my nature makes me prone to. It also helps me correct and avoid them. For I know that all my senses more often inform me falsely than truly about what benefits the body. And I can (almost always) use more than one sense to examine the same thing. I can also use memory, which connects present and past experiences. And I can use my understanding, which has already revealed all the causes of my errors. So I should no longer fear that what my senses show me daily is false. Above all, I should dismiss those extreme doubts from my First Meditation as ridiculous. This applies particularly to the main doubt, namely, * the difficulty of distinguishing sleep from waking. For now I clearly see a great difference between sleep and waking. My dreams are never connected by my memory with the other events of my life. Whatever happens to me while awake is connected in this way. Suppose that, while I was awake, someone suddenly appeared before me and then immediately disappeared, as happens in dreams. Suppose I could not tell where he came from or where he went. I would certainly consider him a ghost or an apparition created in my brain, rather than a real man. But sometimes I clearly know where things come from, where they occur, and when. And my memory lets me connect my perception of these things with the other events of my life. When these conditions hold, I am certain I perceive these things while awake, not asleep. Nor should I have the slightest doubt about their truth, provided they pass a further test. I must call on all my senses, memory, and understanding to examine these perceptions. If I find nothing in any of these faculties that conflicts with other truths, I should not doubt these perceptions. For God is not a deceiver, so it follows that I am not deceived in such matters. But the need to act in everyday affairs does not always leave time for such a careful examination. So I must admit that human life is subject to many errors about particular things. We must therefore acknowledge the weakness of our nature.

FINIS.

THE END.