Further, it has become impossible to strive for the ideal by selecting from the realm of experience a single point and treating it as an archimedean point, as absolutely fixed, and shaping our life from it. Descartes attempted to do this with his "I think," and Kant with his "I ought." But it is very doubtful whether there is an archimedean point in man; whether to make such an assumption is not to over-estimate man. The experience of history shows further that that which some have taken as absolutely primary and axiomatic has been regarded by others as derivative, and has been explained in an entirely different manner. The presentationalist does not deny the actuality of thought, or the naturalistic thinker conscience; but he understands it as a subsidiary phenomenon, and therefore can find no support in it. How then can that overcome all doubt which itself calls forth serious doubt? A whole sphere can be withdrawn from the confusion and used to overcome it just as little as can a single leading point. For the uncertainty with regard to the whole extends far into every individual sphere; and such a sphere may appear, to one in one way, and to another in another. Science is not infrequently treated as though it were enthroned on high, supreme above all the struggles and the doubts of existence, and as though, from its sovereign capacity, it were able to give a secure content of truth to life. It is true that science has much in its forms and in its work which is not the subject of dispute; but that with which we are here concerned--its intrinsic value, its spiritual character, and its place in life as a whole--is by no means a matter beyond dispute. As a matter of fact, every system of life has its own assertion in reference to this problem: to each to know signifies something different and is capable of something different. Whoever decides for one of these assertions concerning the nature of knowing has at the same time made a decision concerning the systems of life. He stands not outside, but in the midst, of the struggle. The same thing holds good with regard to morality, which is often welcomed as a secure refuge from the doubts of science. For, however certain it may be that in this sphere also there is no difference of opinion in respect of many things, as, for example, concerning the goodness or badness of certain types of conduct, still, the more we come to be concerned with principles the more do problems arise. In the immediate present the fact is most unmistakably clear that in this field also the fight does not rage around the interpretation of a given and acknowledged fact, but around the fact itself. What a different purport and meaning morality has in the systems of Religion, Immanent Idealism, Naturalism, Socialism, and Individualism respectively!