The gorilla, the chimpanzee, the orang-outang, and their kind, must look upon man as a feeble and infirm animal, whose strange custom it is to store up his dead. Wherefore?

And this primary disease and all subsequent diseases—are they not perhaps the capital element of progress? Arthritis, for example, infects the blood and introduces into it scoriæ, a kind of refuse, of an imperfect organic combustion; but may not this very impurity happen to make the blood more stimulative? May not this impure blood promote a more active cerebration precisely because it is impure? Water that is chemically pure is undrinkable. And may not also blood that is physiologically pure be unfit for the brain of the vertical mammal that has to live by thought?

The history of medicine, moreover, teaches us that progress consists not so much in expelling the germs of disease, or rather diseases themselves, as in accommodating them to our organism and so perhaps enriching it, in dissolving them in our blood. What but this is the meaning of vaccination and all the serums, and immunity from infection through lapse of time?

If this notion of absolute health were not an abstract category, something which does not strictly exist, we might say that a perfectly healthy man would be no longer a man, but an irrational animal. Irrational, because of the lack of some disease to set a spark to his reason. And this disease which gives us the appetite of knowing for the sole pleasure of knowing, for the delight of tasting of the fruit of the tree of the knowledge of good and evil, is a real disease and a tragic one.

Παντες ανθρωποι τον εἱδεναι ορεγονται φυσει , "all men naturally desire to know." Thus Aristotle begins his Metaphysic, and it has been repeated a thousand times since then that curiosity or the desire to know, which according to Genesis led our first mother to sin, is the origin of knowledge.

But it is necessary to distinguish here between the desire or appetite for knowing, apparently and at first sight for the love of knowledge itself, between the eagerness to taste of the fruit of the tree of knowledge, and the necessity of knowing for the sake of living. The latter, which gives us direct and immediate knowledge, and which in a certain sense might be called, if it does not seem too paradoxical, unconscious knowledge, is common both to men and animals, while that which distinguishes us from them is reflective knowledge, the knowing that we know.

Man has debated at length and will continue to debate at length—the world having been assigned as a theatre for his debates—concerning the origin of knowledge; but, apart from the question as to what the real truth about this origin may be, which we will leave until later, it is a certainly ascertained fact that in the apparential order of things, in the life of beings who are endowed with a certain more or less cloudy faculty of knowing and perceiving, or who at any rate appear to act as if they were so endowed, knowledge is exhibited to us as bound up with the necessity of living and of procuring the wherewithal to maintain life. It is a consequence of that very essence of being, which according to Spinoza consists in the effort to persist indefinitely in its own being. Speaking in terms in which concreteness verges upon grossness, it may be said that the brain, in so far as its function is concerned, depends upon the stomach. In beings which rank in the lowest scale of life, those actions which present the characteristics of will, those which appear to be connected with a more or less clear consciousness, are actions designed to procure nourishment for the being performing them.

Such then is what we may call the historical origin of knowledge, whatever may be its origin from another point of view. Beings which appear to be endowed with perception, perceive in order to be able to live, and only perceive in so far as they require to do so in order to live. But perhaps this stored-up knowledge, the utility in which it had its origin being exhausted, has come to constitute a fund of knowledge far exceeding that required for the bare necessities of living.

Thus we have, first, the necessity of knowing in order to live, and next, arising out of this, that other knowledge which we might call superfluous knowledge or knowledge de luxe, which may in its turn come to constitute a new necessity. Curiosity, the so-called innate desire of knowing, only awakes and becomes operative after the necessity of knowing for the sake of living is satisfied; and although sometimes in the conditions under which the human race is actually living it may not so befall, but curiosity may prevail over necessity and knowledge over hunger, nevertheless the primordial fact is that curiosity sprang from the necessity of knowing in order to live, and this is the dead weight and gross matter carried in the matrix of science. Aspiring to be knowledge for the sake of knowledge, to know the truth for the sake of the truth itself, science is forced by the necessities of life to turn aside and put it itself at their service. While men believe themselves to be seeking truth for its own sake, they are in fact seeking life in truth. The variations of science depend upon the variations of human needs, and men of science are wont to work, willingly or unwillingly, wittingly or unwittingly, in the service of the powerful or in that of a people that demands from them the confirmation of its own desires.

But is this really a dead weight that impedes the progress of science, or is it not rather its innermost redeeming essence? It is in fact the latter, and it is a gross stupidity to presume to rebel against the very condition of life.