in accordance with the facts be able to arise, and men will perceive that the sun emits white light which is split up by the prism into differing rays with different peculiarities, which rays can be recombined by the lens into one mass of white light.
This example shows sufficiently well that the road to Truth leads through far-reaching and comparative observations, the results of which must be controlled by the help of freely chosen experiments, until well-grounded hypotheses and theories can be put forward; but these hypotheses and theories will fall to the ground as soon as a single new observation or experiment contradicts them.
The way is difficult, and in the end all man ever attains to is relative truth. But such relative truth suffices for the time being, if it serves to explain the most important actual concatenations of the past, to light up present problems, to predict those of the future, so that we are then in a position to achieve adaptation through our knowledge. But absolute truth could be accessible only to omniscience, aware of all possible concatenations and combinations; that is not possible, for the concatenations and their combinations are infinite. Accordingly, we shall never know more than an approximate truth. Should now relationships be discovered, new combinations built up, then the picture changes, and with it the entire possibilities in knowledge and power. To what revolutions in daily life does not every new scientific discovery lead: how absurdly little was the beginning of our first ideas of electricity, how inconceivably great the results! Time and again it is necessary to repeat this commonplace, because one sees how life is always made bitter for the innovators in every scientific field, and now is it being made especially so for the disciples of the psychoanalytic school. Of course, every one admits the truth of this platitude so long as it is a matter of "academic" discussion, but only so long; just as soon as a concrete case has to be considered, sympathies and antipathies rush into the foreground and darken judgment. And therefore the scientist must fight tirelessly, appealing to logic and honour, for freedom of research in every field, and
