In this way, however, the revolutionary side of Hegelian philosophy was again taken up and at the same time freed from the idealist trimmings which with Hegel had prevented its consistent execution. The great basic thought that the world is not to be comprehended as a complex of ready made things, but as a complex of processes, in which the things apparently stable no less than their mind images in our heads, the concepts, go through an uninterrupted change of coming into being and passing away, in which, in spite of all seeming accidentally and of all temporary retrogression, a progressive development asserts itself in the end — this great fundamental thought has, especially since the time of Hegel, so thoroughly permeated ordinary consciousness that in this generality it is now scarcely ever contradicted. But to acknowledge this fundamental thought in words and to apply it in reality in detail to each domain of investigation are two different things. If, however, investigation always proceeds from this standpoint, the demand for final solutions and eternal truths ceases once for all; one is always conscious of the necessary limitation of all acquired knowledge, of the fact that it is conditioned by the circumstances in which it was acquired. On the other hand, one no longer permits oneself to be imposed upon by the antithesis, insuperable for the still common old metaphysics, between true and false, good and bad, identical and different, necessary and accidental. One knows that these antitheses have only a relative validity; that that which is recognized now as true has also its latent false side which will later manifest itself, just as that which is now regarded as false has also its true side by virtue of which it could previously be regarded as true. One knows that what is maintained to be necessary is composed of sheer accidents and that the so-called accidental is the form behind which necessity hides itself — and so on.