Page:Schlick - Gesammelte Aufsätze (1926 - 1936), 1938.djvu/273

 It would be best to banish the words "phaenomenon" and, "appearance" from philosophy altogether, there are very few thinkers who have not been led astray by them.

If there is anything in the world of our experience that "points to" anything else — that is, if the truth of our propositions makes us believe in the truth of another one without there being any logical connection between the two-then the inferred reality must be of the same kind as the one from which it is inferred, we must be able to experience it, or, in short, to perceive it in some way or other.

Suppose I have a closed box and hear a rattling noise every time I shake it: I infer that when the box is opened I shall "see stones" or, when I put my hand into it, shall "touch certain hard objects". These inferences can easily be verified and no objections can be raised if I call the rattling noise a "phaenomenon" and the stones the "reality" which is responsible for the appearance of the noise. But evidently the rattling is just as real as the sight or touch of the stones; they are, all of them physical processes correlated in a certain way, and whatever inferences may be drawn concerning the box and its contents — they will always lead to physical processes, empirical facts, and cannot lead to anything "beyond", to metaphysical things.

It is worth noticing that the arguments which prove the existence of physical entities like atoms or electrons are of exactly the same nature as those which make us believe that there are stones in our rattling box. Even when there are no stones in a box, the physicist observes certain symptoms which make him declare that it is not empty, but full of air, and that the air consists of molecules, and so on. It is true, we do not say that we "perceive" the molecules in the same way as we do the stones: nevertheless the verification of the existence of atoms or other physical entities is not essentially different from the case of visible and tangible objects, it would not even be correct to say that the chain of reasoning is longer in one case, shorter in the other. Atoms, therefore, are empirical entities just like stones, and just as real. In fact the physicist has a right to say that "stone" in nothing but a name for a complex of atoms, and that we have just as much knowledge of stones (and no more) than we have of the atoms of which they are composed.

This illustrations show that the supposed transition from a known ap-