gions in the world. In the course of the self-examination of our philosopher, the plummet of doubt reaches so deep that it penetrates to, and vindicates the possibility of, this conception, and thus demolishes the last bulwark, behind which our ordinary beliefs, nourished by our confidence in the senses, have protected themselves from scepticism. We have, therefore, no beliefs that cannot and must not be doubted, if we wish to completely rid ourselves of every selfdelusion. It may be that many of them are true; but we do not know it, since none of them are proved. We have no reason to consider them certain, but reason enough to hold them uncertain. Now, the declaration, "I doubt every thing," follows from the perception of this universal uncertainty. "What can I allege against these reasons? I have no arguments to weaken their force. I am at last compelled to the open acknowledgment, that every thing which I have believed can be doubted, not thoughtlessly or lightly, but from cogent and well-considered reasons; and that, if the truth is of any importance to me, I ought to guard as carefully against assuming by chance that which is uncertain, as that which is plainly false."1

II. DOUBT AS METHOD AND AS PRINCIPLE.

With our entire world of conceptions which has not stood the test of self-examination- we are prisoners to selfdelusion, and have grown accustomed to our fetters. Doubt requires not only to break in upon and attack this habit here and there, but all along the line, that it may utterly destroy it it requires to wean us from the habit of self-delusion. No habit is stronger than that of belief, and none is more difficult to get rid of. And if doubt is really to have the power to banish self-delusion, it is not enough for us to conceive and understand it, and have a distinct idea of the reasons for it: we must accustom ourselves to this mode of thought, and live in this critical state of mind as heretofore

1 Méd., p. 242. Princ., i. sec. 2. Rech., p. 351.

in the uncritical. That is as difficult as this was easy. The habit of self-delusion comes of itself; the weaning from it only through discipline of the mind and method. "But it is not enough by far to have observed this necessity: we must continually re-present it to our minds. For those familiar opinions are constantly returning and capturing the easily believing mind, which is subject to them, as it were, by prescription and domestic right. They return against my will, and I cannot wean myself from the habit of deferring to them, and confiding in them. Although I know very well how doubtful they are, nevertheless they seem so true that it seems more reasonable to believe them than deny them."1

Doubt becomes a principle: the critical direction of the mind becomes a conscious resolution of the will and a maxim. I wish to get rid of self-delusion, and not merely in this case or that, here or now, but in all cases and at all times. As self-deception is universal and habitual, so the doubt which is to banish it must be universal, and become at home in our mode of thought. We should note carefully the object of this doubt. It is not directed against this or that conception, the religious conception, for example, of which many first think when doubt is spoken of, but against a human state, the existence of which we can see with half an eye, against the state of self-delusion, imagination, blindness. He who rejects or opposes the doubt of Descartes, must approve of our self-delusion. He who holds it better not to give way to that doubt, must hold it better for us to continue in our self-blindness. It can, therefore, be only a deluded mind, not one that is earnestly religious, that fears such doubt. The opposite of self-delusion is truthfulness to one's self. This is the source of all truth and all the courage in seeking truth. He who is not true to himself has not the courage to look through his blindness; he has in general no courage in seeking truth; generally speaking, he is not true, and all the candor which he has in other matters

1 Méd., i. pp. 242, 243.

is at bottom false. That, therefore, is the intention of the Cartesian doubt and the task which it sets itself: be true to yourself. Do not persuade yourself, and do not allow yourself to be persuaded, that you are what you are not, that you know what is not clear and evident to you, that you believe that which at bottom you doubt, or ought to doubt.

Thus deeply inward is the inquiring and critical mind of Descartes directed: he requires self-illumination in place of self-delusion. He has to do only with his own mind, and not with the world; his doubt attacks merely the validity of conceptions, and not states of the world; it is therefore not practical, but only theoretical. "I know that neither danger nor error can arise from this: I have no reason to be afraid of an excess of distrust, since I am here concerned, not with practical, but merely with theoretical, problems. I will suppose, then, not that the All-wise and perfectly good God is the source of truth, but some malignant, and at the same time powerful, demon, who has employed all his skill in deceiving me. I will suppose that the sky, the air, the earth, colors, figures, sounds, and all the things I perceive without me, are the illusions of dreams, with which that spirit has laid snares for my credulity. I will consider myself as without eyes, flesh, blood, or any of the senses, as possessing all these things merely in imagination, and I will resolutely continue and strengthen myself in this mode of consideration. If it is not then in my power to arrive at the knowledge of truth, I shall at least be able to protect myself from error. I will face that lying spirit, and be he ever so powerful and cunning, he shall not overcome me. undertaking is difficult, and a certain indolence is constantly leading me back to my old habits of life and like a prisoner who rejoices in dreams over an imaginary freedom, and dreads awakening, when he begins to suspect that it is only a dream, and cherishes the pleasant fancy as long as possible, so involuntarily I fall back into my old beliefs, and fear to arouse myself from my slumber. I fear the laborious exist

But the

1

ence that will follow this pleasant sleep, and which must be spent, not in the light of day, but in the impenetrable darkness of already excited doubts." To return is impossible. The sun of truth must rise out of the ocean of doubt itself.

1 Méd., i. pp. 243-245. Pr., i. 3, p. 64.

CHAPTER III.

THE PRINCIPLE OF PHILOSOPHY AND THE PROBLEM OF KNOWLEDGE.

I

I. THE PRINCIPLE OF CERTAINTY.

1. One's Own Thinking Being.

HAVE no conception the truth of which is evident to me. On the contrary, they are all of such a nature that I perceive their uncertainty. Experience, which has contradicted them in so many cases, testifies against the transmitted conceptions of childhood; the errors of the senses against the conceptions of sense; dreams, against the apparently most certain sense-perceptions; and, finally, against the reality of those elementary conceptions that lie at the foundation of all the rest, arises the possibility that the world of the senses universally is a mere unsubstantial, phantom world, that in the very roots of our being we are involved in deception and illusion. Thus, every thing is doubtful, and nothing certain except this very doubt. Every thing is doubtful; i.e., I doubt every thing. The second proposition is as certain as the first, and I am as certain of myself. If I subtract delusion from self-delusion, myself remains: if that is possible, this is necessary. Without a self, there can be no self-delusion and no doubt. Now I have found a point which doubt can never attack, because it depends upon it. "Archimedes demanded only a firm and immovable point in order to move the earth, and we also can entertain great hopes if we can discover the smallest certain and indubitable truth." Even suppose that