Page:Mind (New Series) Volume 9.djvu/405

 JOSEPH PETZOLDT, 1'hiio -,' Rrinen Erfalirnit-i. doubt be given that it must be understood as the effect of certain causes. If so, proceeds our author, the causes must be of a psychical kind, for the idea of a physical cause bringing about psychical effects has long ago been exploded. On the assumption that we acquiesce in this Mr. Petzoldt proceeds to enlighten us. He attempts to show (1) that the facts upon which the time-worn principle of causation is founded do not justify us in admitting more or less than the unideterminateness of all that happens ; (2) that the psychical states being non-unideterminable by each other, the attempt to make them explain one another is scientifi- cally unthinkable ; (3) that the only way out of the difficulty is to accept the doctrine of psycho-physical parallelism in the sense of Avenarius. The causal idea in its old form is, according to Mr. Petzoldt, quite untenable. Taking a concrete example, that of the fall of an avalanche, our author shows how the attempts to define the causal relation more closely, first by distinctions into direct causes and indirect conditions, then by analysis of these into their component factors, are doomed to failure on account of the continuity of natural events. It is impossible in short to give a clear, sharply-defined meaning to the terms cause and effect. Science is therefore bound to forsake these concepts and this it does the more willingly when an inquiry into their origin shows them to be in all their aspects mere relics of animism. Of these aspects that of necessary connexion between cause and effect is the most important and misleading. It is a mere anthropomor- phism. The necessary is in fact a bewildering expression for the actual and nothing more. In consequence of the complete unsatisfactoriness of these causal concepts Mr. Petzoldt starts an inquiry into the nature of the facts upon which they are based. This fact he finds to be simply the following, that every natural event is fully determined in all its parts. It is in giving precision to this fundamental statement that Mr. Petzoldt reaches the central conception of unideterminateness. He first of all takes a number of examples by way of illustra- tion and shows by means of these that whenever there are a number of possible ways in which, say, the movement of a body would be directed, that part is selected, as a matter of fact, which possesses the following three elements of unideterminateness : (1) singleness of direction, (2) uniqueness, (3) continuity, for in satisfying these three conditions all indeterminateness is taken from its changes. The meaning of the first determining element is simply this that as a matter of fact there is no actual ambiguity as to the sense in which any change takes place. Warm bodies left to themselves always grow cooler ; heavy bodies left to themselves always fall downwards not upwards. A first con- ceivable ambiguity is thus put to rest by Nature herself. In the second place Nature takes care that bodies shall move in such a way relatively to their Bestimmungsmittel or media of determina-