METAPHYSICS is Second, Evolution is Third’ (EWP 173) Moreover, he offered an elaborate proof that while a scientific language must contain monadic, dyadic, and triadic predicates, there are no phenomena that require four-place predicates for their expression Expressions containing such predicates can always be translated into expressions containing only predicates of the three basic kinds Thirdness, however, Peirce sees as an irreducible element of the universe, neglected by nominalist philosophers, who refused to accept the reality of universals The aim of all scientific inquiry is to find the thirdness in the variety of our experience—to discover the patterns, regularities, and laws in the world we live in But we should not be looking for universal, exceptionless laws that determine all that happens The doctrine of necessity, indeed, was one of Peirce’s chief targets in his criticism of the Weltanschauung of nineteenth-century science He states it thus: The proposition in question is that the state of things existing at any time, together with certain immutable laws, completely determine the state of things at every other time (for a limitation to future time is indefensible) Thus, given the state of the universe in the original nebula, and given the laws of mechanics, a sufficiently powerful mind could deduce from these data the precise form of every curlicue of every letter I am now writing (EWP 176) This proposition, Peirce thought, was quite indefensible It could be put forward neither as a postulate of reasoning nor as the outcome of observation ‘Try to verify any law of nature and you will find that the more precise your observations, the more certain they will be to show irregular departures from the law’ (EWP 182) Peirce maintained that there was an irreducible element of chance in the universe: a thesis which he called ‘tychism’ from the Greek word for chance, ụữỗ In support of tychism he enlisted both Aristotle and Darwin The inclusion of chance as a possible cause, he said, was of the utmost essence of Aristotelianism; and the only way of accounting for the laws of nature was to suppose them results of evolution ‘This supposes them not to be absolute, not to be obeyed precisely It makes an element of indeterminacy, spontaneity, or absolute chance in nature’ (EWP 163) Thus, there was ample room for belief in the autonomy and freedom of the human will There were, Peirce thought, three ways of explaining the relationship between physical and psychical laws The first was neutralism, which 182