Indeterminism

Abstract: The connection between causation and necessity was reinforced. And this has been the general characteristic of those who have sought to oppose David Hume's conception of causality. It is often declared or evidently assumed that causality is some kind of necessary connection, or alternatively, that being caused is—nontrivially—in stancing some exceptionless generalization saying that such an event always follows such antecedents. The truth of physical indeterminism is thus indispensable if people are to make anything of the claim to freedom. But certainly it is insufficient. The physically undetermined is not thereby 'free'. For freedom at least involves the power of acting according to an idea, and no such thing is ascribed to whatever is the subject of unpredetermination in indeterministic physics. It was natural that when physics went indeterministic, some thinkers should have seized on this indeterminism as being just what was wanted for defending the freedom of the will.

Abstract: According to quantum theory, measurements generate random outcomes, in stark contrast with classical mechanics. This raises the question of whether there could exist an extension of the theory that removes this indeterminism, as suspected by Einstein, Podolsky and Rosen. Although this has been shown to be impossible, existing results do not imply that the current theory is maximally informative. Here we ask the more general question of whether any improved predictions can be achieved by any extension of quantum theory. Under the assumption that measurements can be chosen freely, we answer this question in the negative: no extension of quantum theory can give more information about the outcomes of future measurements than quantum theory itself. Our result has significance for the foundations of quantum mechanics, as well as applications to tasks that exploit the inherent randomness in quantum theory, such as quantum cryptography.

Abstract: Karl R Popper 1982 London: Hutchinson xxii + 185 pp price £15 This is the second volume of Sir Karl Popper's long-awaited Postscript to The Logic of Scientific Discovery, which in the 25 years since its composition has only been available in unpublished form to a small circle. Its publication today, through the work of W W Bart ley III as editor, is a major addition to Popper's corpus and deserves wide attention.

Abstract: People's concept of free will is often assumed to be incompatible with the deterministic, scientific model of the universe. Indeed, many scholars treat the folk concept of free will as assuming a special form of nondeterministic causation, possibly the notion of uncaused causes. However, little work to date has directly probed individuals' beliefs about what it means to have free will. The present studies sought to reconstruct this folk concept of free will by asking people to define the concept (Study 1) and by confronting them with a neuroscientific claim that free will is an illusion (Study 2), which invited them to either reconcile or contrast free will with determinism. The results suggest that the core of people's concept of free will is a choice that fulfills one's desires and is free from internal or external constraints. No evidence was found for metaphysical assumptions about dualism or indeterminism.