But before we begin our study, let us remember a rule of the great orator and philosopher of ancient Rome; a rule only too often forgotten in our times: “Every philosophical discussion, of anything whatsoever, should begin with a definition, in order to make clear what the discussion is about” (_Cicero_, De Officiis, I, 2). If we would form a judgment as to the demand of science for freedom, as to the justification of this demand, as to its compatibility or incompatibility with the duty of faith, the first question that naturally arises is: What is the purport of this demand, what does it mean? Only after we have clearly circumscribed this demand can we approach its philosophical presumptions and test its basis. What, then, do we understand by Science, and what freedom may be granted to it? Science. When a man of Northern or Central Europe hears of science, his thoughts generally turn to the universities and their teachers. To him the university is the home of science, there its numerous branches dwell in good fellowship, there hundreds of men have consecrated themselves to its service. In those parts of Europe it is customary for men of science to be university professors. Of what university is he? is asked. Celebrated scientists, like _Helmholtz_, _Liebig_, _Hertz_, _Kirchhoff_; philosophers, like _Kant_, _Fichte_, _Schelling_, _Hegel_, _Herbart_; great philologists, historians, and so on, were university professors. For all that, _science_ and _university_ are not necessarily inseparable things. The university needs science, but science does not absolutely need the university. Science was in the world before the twelfth and thirteenth centuries, the time when France and Italy built their first universities; and also since then science has been enriched by the achievements of many a genius who never occupied a university chair. _Pythagoras_, _Aristotle_, _St. Augustine_ belonged to no universities; _Copernicus_, _Newton_, and _Kepler_ never taught in the higher schools. In the countries of Western Europe and America the man of science and the university professor are to this day not so much identical in person. Therefore, if the freedom of science applies _principally_ to the higher schools and their teachers, this is not its exclusive application. Science and university are not identical terms. What, then, is science? At the sound of this magic word there arises in the minds of many the image of a superhuman being: open on his lap lies the book of wisdom in which all mysteries are solved; in his hand is the flaming torch which enlightens the path down into the lowest depths of research, dispelling all darkness. This, in the minds of many, is what science means. The mere appeal to this infallible being suffices to settle all problems, to silence every contradiction; woe to him who dares open his profane mouth to utter an If or a But!