Page:Landmarks of Scientific Socialism-Anti-Duehring-Engels-Lewis-1907.djvu/122

 human race, that is endless as far as we are concerned. In this sense human thought is just as sovereign as not—sovereign, and its possibility of knowledge just as unlimited as limited. It is sovereign and unlimited as regards its nature, its significance, its possibilities, its historical end, it is not sovereign and limited with respect to individual expression and its actuality at any particular time.

It is just the same with eternal truths. If mankind only operated with eternal truths and with thought which possessed a sovereign significance and unlimited claims to truth, mankind would have arrived at a point where the eternity of thought becomes realised in actuality and possibility. Thus the famous miracle of the enumerated innumerable would be realised.

But what about those truths which are so well established that to doubt them is to be, as it were, crazy? That twice two is four, that the three angles of a triangle are equal to two right angles, that Paris is in France, that a man will die of hunger if he does not receive food, etc? Do we not perceive then that there are eternal truths, final truths of last instance? Quite so. We can divide the entire field of knowledge in the old-fashioned way into three great divisions. The first includes all the sciences which are concerned with inanimate nature and which can be treated mathematically, more or less—mathematics, astronomy, mechanics, physics and chemistry. If one like to use big words to express simple things, it may be said that certain results of these sciences are eternal truths, final truths of last instance, whence they are called the exact sciences. But all the results are by no means of this character. With the introduction of variable quantities and the extension of the variability to the infinitely small and the infinitely