Things That Can Be Doubted

Some years past I perceived how many Falsities I admitted as Truths in my Younger years, and how Dubious those things were which I raised from thence; and therefore I thought it requisite (if I had a designe to establish any thing that should prove firme and permanent in sciences) that once in my life I should clearly cast aside all my former opinions, and begin a new from some First principles. But this seemed a great Task, and I still expected that maturity of years, then which none could be more apt to receive Learning; upon which Account I waited so long, that at last I should deservedly be blamed had I spent that time in Deliberation which remain’d only for Action.

Some years ago, I realized how many falsehoods I had accepted as truths in my youth. I also realized how doubtful the ideas I had built on those beliefs were. So I thought I needed, once in my life, to set aside all my former opinions completely. This was necessary if I wanted to establish anything firm and lasting in the sciences. I would have to begin again with some first principles. But this seemed a great task. I kept waiting until I reached an age when I would be as ready as possible for learning. Because of this, I waited so long that I would now deserve blame for spending more time in deliberation. The time I had left was for action alone.

This day therefore I conveniently released my mind from all cares, I procured to my self a Time Quiet, and free from all Business, I retired my self Alone; and now at length will I freely and seriously apply my self to the General overthrow of all my former Opinions.

So today I cleared my mind of all worries and set aside some quiet time, free from all work. I withdrew to be alone. Now, at last, I will freely and seriously devote myself to overturning all my former opinions.

To the Accomplishment of Which, it will not be necessary for me to prove them all false (for that perhaps I shall never atcheive) But because my reason perswades me, that I must withdraw my assent no less from those opinions which seem not so very certain and undoubted, then I should from those that are Apparently false, it will be sufficient if I reject all those wherein I find any Occasion of doubt.

To achieve this, I will not need to prove all these opinions false. (Perhaps I will never manage that.) But my reason convinces me to withhold belief from opinions that seem less than fully certain and beyond doubt. I must do so just as I would with opinions that are clearly false. So I need only reject all opinions in which I find any reason for doubt.

Neither to effect this is it necessary, that they all should be run over particularly (which would be an endles trouble) but because the Foundation being once undermin’d, whatever is built thereon will of its own accord come to the ground, I shall therefore immediately assault the very principle, on which whatever I have believed was grounded. Viz.

To do this, I do not need to examine all my beliefs individually. That would be an endless task. But once the foundation is undermined, everything built on it will collapse on its own. So I will immediately attack the very principle on which all my beliefs were based. Namely:

Whatever I have hitherto admitted as most true, that I received either from, or by my Senses; but these I have often found to deceive me, and ’tis prudence never certainly to trust those that I have (tho but once) deceived us.

Everything I have so far accepted as most true has come from or through my senses. But I have often found that my senses deceive me. It is wise never to trust completely those who have deceived us (even once).

1 Doubt. But tho sometimes the senses deceive us being exercised about remote or small objects, yet there are many other things of which we cannot doubt tho we know them only by the senses? as that at present I am in this place, that I am sitting by a fire, that I have a Winter gown on me, that I feel this Paper with my hands; But how can it be denied that these hands or this body is mine? Unless I should compare my self to those mad men, whose brains are disturbed by such a disorderly melancholick vapour, that makes them continually profess themselves to be Kings, tho they are very poor, or fancy themselves cloathed in Purple Robes, tho they are naked, or that their heads are made of Clay as a bottle, or of glass, &c. But these are mad men, and I should be as mad as they in following their example by fancying these things as they do.

1 Doubt. But although the senses sometimes deceive us about distant or small objects, aren’t there many other things we cannot doubt? We know these things only through our senses. For example, I am here now, sitting by a fire, wearing a winter gown, and feeling this paper with my hands. But how can anyone deny that these hands or this body belong to me? I could deny it only by comparing myself to madmen whose brains are disturbed by an unruly, melancholy vapor. This vapor makes them constantly claim to be kings, though they are very poor. Or they imagine themselves dressed in purple robes, though they are naked. Or they imagine their heads are made of clay, like a bottle, or of glass, and so on. But these men are mad. And I would be just as mad if I followed their example and imagined such things myself.

1 Solution. This truly would seem very clear to those that never sleep, and suffer the same things (and sometimes more unlikely) in their repose, then these mad men do whilst they are awake; for how often am I perswaded in a Dream of these usual occurrences, that I am in this place, that I have a Gown on me, that I am sitting by a fire, &c. Tho all the while I am lying naked between the Sheets.

1 Solution. This would indeed seem very clear to those who never sleep. Yet in sleep, we experience the same things these madmen experience while awake (and sometimes even less likely things). For how often am I convinced in a dream that I am doing ordinary things? I am here, wearing a gown, sitting by a fire, and so on. Though all the while, I am lying naked between the sheets.

But now I am certain that I am awake and look upon this Paper, neither is this head which I shake asleep, I knowingly and willingly stretch out this hand, and am sensible that things so distinct could not happen to one that sleeps. As if I could not remember my self to have been deceived formerly in my sleep by the like thoughts; which while I consider more attentively I am so far convinced of the difficulty of distinguishing sleep from waking that I am amazed, and this very amazement almost perswades me that I am asleep.

But now I am certain that I am awake and looking at this paper. Nor is the head I am shaking asleep. I stretch out my hand knowingly and willingly. I am aware that experiences so clear could not happen to someone asleep. As if I could not remember being fooled by similar thoughts in my sleep before. But as I consider this more carefully, I become so convinced that distinguishing sleep from waking is difficult that I am amazed. And this very amazement almost persuades me that I am asleep.

2 Doubt. Wherefore let us suppose our selves asleep, and that these things are not true, viz. that we open our eyes, move our heads, stretch our hands, and perhaps that we have no such things as hands or a body. Yet we must confess, that what we see in a Dream is (as it were) a painted Picture, which cannot be devised but after the likeness of some real thing; and that therefore these Generals at least, viz. eyes, head, hands, and the whole body are things really existent and not imaginary; For Painters themselves, (even then when they design Mermaids and Satyrs in the most unusual shapes) do not give them natures altogether new, but only add the divers Parts of different Animals together; And if by chance they invent any thing so new that nothing was ever seen like it, for that ’tis wholy fictitious and false, yet the colours at least of which, they make it must be true Colours; so upon the same account, tho these General things as eyes, head, hands, &c. may be imaginary; yet nevertheless we must of necessity confess the more simple and universal things to be True, of which (as of true Colours) these Images of things (whether true or false) which are in our minds are made; such as are the nature of a body in General, and its Extension, also the shape of things extended, with the quantity or bigness of them; their number also, and place wherein they are, the time in which they continue, and the like, and therefore from hence we make no bad conclusion, that Physick, both Natural, and Medicinal, Astronomy, and all other sciences, which depend on the consideration of compound things, are Doubtful. But that Arithmetick, Geometry, and the like (which treat only of the most simple, and General things not regarding whether they really are or not) have in them something certain and undoubted; for whether I sleep or wake, two and three added make five; a square has no more sides than four &c. neither seems it possible what such plain truths can be doubted off.

2 Doubt. So let us suppose we are asleep, and that these things are not true. That is, we are not opening our eyes, moving our heads, or stretching out our hands. Perhaps we do not even have hands or a body. Yet we must admit that what we see in a dream is like a painted picture. Such a picture can only be created in the likeness of something real. So at least these general things, namely eyes, heads, hands, and whole bodies, really exist and are not imaginary. For even when painters depict mermaids and satyrs in the strangest forms, they do not create entirely new natures. They merely combine different parts of different animals. And perhaps painters invent something so new that nothing like it has ever been seen, something wholly fictional and false. Even then, at least the colors they use to create it must be real colors. So, by the same reasoning, although general things like eyes, heads, hands, and so on may be imaginary, something remains. We must still admit that the more simple and universal things are real. These simpler things are like real colors. The images of things in our minds, whether true or false, are made from them. These include the nature of body in general and its extension, or the space it occupies. They also include the shape of extended things, their quantity or size, and their number. They include the place those things occupy, the time they last, and the like. So we can reasonably conclude that physics, both natural philosophy and medicine, astronomy, and all other sciences concerned with complex things are doubtful. But arithmetic, geometry, and similar subjects contain something certain and beyond doubt. These subjects deal only with the simplest and most general things, regardless of whether those things actually exist. For whether I am asleep or awake, two plus three makes five. A square has no more than four sides, and so on. Nor does it seem possible to doubt such obvious truths.

2 Solution. But all this While there is rooted in my mind a certain old opinion of the being of an Omnipotent God, by whom I am created in the state I am in; and how know I but he caused that there should be no Earth, no Heaven, no Body, no Figure, no Magnitude, no Place, and yet that all these things should seem to me to be as now they are? And as I very often judge others to Erre about those things which they think they Throughly understand, so why may not I be deceived, whenever I add two and three, or count the sides of a Square, or whatever other easy Matter can be thought of?

2 Solution. But throughout all this, an old belief remains firmly rooted in my mind. I believe in the existence of an Almighty God, who created me in my present state. How do I know he has not made it so that no earth, heaven, body, shape, size, or place exists? Yet he could make all these things seem to me to exist just as they do now. I very often judge that others are mistaken about things they think they fully understand. So why might I not be deceived whenever I add two and three, or count the sides of a square? Or whenever I consider any other equally simple matter?

3. Doubt. But perhaps God wills not that I should be deceived, for he is said to be Infinitely Good.

3. Doubt. But perhaps God does not want me to be deceived, because he is said to be Infinitely Good.

3. Solution. Yet if it were Repugnant to his Goodness to create me so that I should be always deceived, it seems also unagreeable to his Goodness to permit me to be deceived at any time; Which last no one will affirme: Some there are truely who had rather deny Gods Omnipotence, then beleive all things uncertain; but there at present we may not contradict. And we will suppose all this of God to be false; yet whether they will suppose me to become what I am by Fate, by Chance, by a continued chain of causes, or any other way, because to erre is an Imperfection, by how much the less power they will Assigne to the Author of my Being, so much the more Probable it will be, that I am so Imperfect as to be alwayes deceived.

3. Solution. Yet suppose it were contrary to his goodness to create me so that I should be always deceived. It also seems contrary to his goodness to allow me to be deceived at any time. Yet no one will assert this last claim. Some people would indeed rather deny God’s omnipotence than believe all things uncertain. But for now, we need not challenge these people. Let us suppose that all these claims about God are false. These people might suppose that I became what I am through fate, chance, a continuous chain of causes, or some other means. But to err is an imperfection. So the less power they assign to the creator of my being, the more probable it becomes that I am so imperfect as to be always deceived.

To which Arguments I know not what to answer but am forced to confess, that there is nothing of all those things which I formerly received as Truths, whereof at present I may not doubt; and this doubt shall not be grounded on inadvertency or Levity, but upon strong and Premeditated reasons; and therefore I must hereafter (if I designe to discover any truths) withdraw my assent from them no less then from apparent falshoods.

I do not know how to answer these arguments, but I must admit something. There is nothing among all the things I once accepted as truths that I cannot now doubt. This doubt is not based on carelessness or a lack of seriousness, but on strong, carefully considered reasons. So, if I intend to discover any truths, I must now withhold my acceptance of those former beliefs. I must do so just as firmly as I would with obvious falsehoods.

But ’tis not sufficient to think only Transiently on these things, but I must take care to remember them; for dayly my old opinions returne upon me, and much against my Will almost possesse my Beleife tyed to them, as it were by a continued use and Right of Familiarity; neither shall I ever cease to assent and trust in them, whilst I suppose them as in themselves they really are, that is to say, something doubtful (as now I have proved) yet notwithstanding highly Probable, which it is much more Reasonable to beleive then disbeleive.

But it is not enough to think about these things only briefly. I must take care to remember them. For every day my old opinions return and almost take over my beliefs, much against my will. My beliefs seem bound to these opinions by constant use and the Right of Familiarity. Nor will I ever stop accepting and trusting these opinions as long as I regard them as they really are. That is, they are somewhat doubtful, as I have now proved, but still highly probable. It is much more reasonable to believe them than to disbelieve them.

Wherefore I conceive I should not do amiss, if (with my mind bent clearly to the contrary side) I should deceive my self, and suppose them for a While altogether false and Imaginary; till at length the Weights of prejudice being equal in each scale, no ill custome may any more Draw my Judgement from the true Conception of things, for I know from hence will follow no dangerous Error, and I can’t too immoderately pamper my own Incredulity, seeing What I am about, concernes not Practice but Speculation.

So I think I would do well to deceive myself by deliberately turning my mind toward the opposite view. I should suppose them entirely false and Imaginary for a while, until the weights of prejudice balance each other. Then no bad habit will draw my judgment away from a true understanding of things. For I know that no dangerous error will result, and I cannot indulge my own doubt too much. What I am doing concerns not Practice but Speculation.

To Which end I will suppose, not an Infinitely perfect God, the Fountain of truth, but that some Evil Spirit which is very Powerful and crafty has used all his endeavours to deceive me; I will conceive, the Heavens, Air, Earth, Colours, Figures, Sounds, and all outward things are nothing else but the delusions of Dreams, by which he has laid snares to catch my easy beleif; I will consider my self as not having hands, Eyes, Flesh, Blood, or Sences, but that I falsely think that I have all these; I will continue firmly in this Meditation; and tho it lyes not in my power to discover any truth, yet this is in my power, not to assent to Falsities, and with a strong resolution take care that the Mighty deceiver (tho never so powerful or cunning) impose not any thing on my beleife.

For this purpose, I will suppose there is no infinitely perfect God, the source of truth. Instead, some Evil Spirit, very powerful and cunning, has done everything he can to deceive me. I will imagine that the heavens, air, earth, colors, shapes, sounds, and all external things are merely dreamlike illusions. Through these illusions, he has set traps for my trusting mind. I will consider myself as having no hands, eyes, flesh, blood, or senses. Instead, I falsely think that I have all these. I will remain firm in this meditation. And though I cannot discover any truth, I can refuse to accept falsehoods. With firm resolve, I will make sure the mighty deceiver imposes no belief on me, however powerful or cunning he may be.

But this is a laborious intention, and a certain sloth reduces me to the usual course of life, and like a Prisoner who in his sleep perhaps enjoy’d an imaginary liberty, and when he begins to suppose that he is asleep is afraid to waken, but is willing to be deceived by the Pleasant delusion; so I willingly fall into my opinions, and am afraid to be Roused, least a toilsome waking succeeding a pleasant rest I may hereafter live not in the light, but in the confused darkness of the doubts now raised.

But this effort is exhausting, and a certain laziness draws me back to my usual way of life. I am like a prisoner who perhaps enjoyed an imaginary freedom in his sleep. When he begins to suspect he is asleep, he fears waking and willingly accepts the pleasant delusion. In the same way, I willingly fall back into my opinions and fear being awakened. I fear that a difficult awakening after a pleasant rest may leave me living not in the light. Instead, I may live in the confused darkness of the doubts now raised.