And he arrives at the cogito ergo sum, which St. Augustine had already anticipated; but the ego implicit in this enthymeme, ego cogito, ergo ego sum, is an unreal—­that is, an ideal—­ego or I, and its sum, its existence, something unreal also.  “I think, therefore I am,” can only mean “I think, therefore I am a thinker”; this being of the “I am,” which is deduced from “I think,” is merely a knowing; this being is knowledge, but not life.  And the primary reality is not that I think, but that I live, for those also live who do not think.  Although this living may not be a real living.  God! what contradictions when we seek to join in wedlock life and reason!

The truth is sum, ergo cogito—­I am, therefore I think, although not everything that is thinks.  Is not consciousness of thinking above all consciousness of being?  Is pure thought possible, without consciousness of self, without personality?  Can there exist pure knowledge without feeling, without that species of materiality which feeling lends to it?  Do we not perhaps feel thought, and do we not feel ourselves in the act of knowing and willing?  Could not the man in the stove have said:  “I feel, therefore I am”? or “I will, therefore I am”?  And to feel oneself, is it not perhaps to feel oneself imperishable?  To will oneself, is it not to wish oneself eternal—­that is to say, not to wish to die?  What the sorrowful Jew of Amsterdam called the essence of the thing, the effort that it makes to persist indefinitely in its own being, self-love, the longing for immortality, is it not perhaps the primal and fundamental condition of all reflective or human knowledge?  And is it not therefore the true base, the real starting-point, of all philosophy, although the philosophers, perverted by intellectualism, may not recognize it?

And, moreover, it was the cogito that introduced a distinction which, although fruitful of truths, has been fruitful also of confusions, and this distinction is that between object, cogito, and subject, sum.  There is scarcely any distinction that does not also lead to confusion.  But we will return to this later.

For the present let us remain keenly suspecting that the longing not to die, the hunger for personal immortality, the effort whereby we tend to persist indefinitely in our own being, which is, according to the tragic Jew, our very essence, that this is the affective basis of all knowledge and the personal inward starting-point of all human philosophy, wrought by a man and for men.  And we shall see how the solution of this inward affective problem, a solution which may be but the despairing renunciation of the attempt at a solution, is that which colours all the rest of philosophy.  Underlying even the so-called problem of knowledge there is simply this human feeling, just as underlying the enquiry into the “why,” the cause, there is simply the search for the “wherefore,” the end.  All the rest is either to deceive oneself or to wish to deceive others; and to wish to deceive others in order to deceive oneself.