Philip Pettit

In a now famous thought experiment, Frank jackson asked us t0 imagine an omniscient scientist, Mary, who is coniincd in a black-and-white room and then released into the world 0f color . Assuming that she is omniscicnt in respect of all physical facts—roughiy, all the facts available to physics and all the facts that they in turn Hx or determine-physicalism would suggest that there is no new fact Mary can discover after emancipation; physicalism holds that all facts are physical in the relevant sense . Yet we cannot help but feel that coming out of that room would be an occasion of dramatic enlightenment and, in particular, an occasion for learning facts to do with how red or yellow or blue 100ks or, as it is usually said, with what it is like t0 sec red or yellow or blue. Many in the black-and—whit

Hobbes made a distinctive contribution to the discussion of freedom on two fronts. He persuaded later, if not immediate, successors that it is only the exercise of a power of interference that reduces people’s freedom, not its (unexercised) existence - not even its existence in an arbitrary, unchecked form. Equally, he persuaded them that the exercise of a power of interference always reduces freedom in the same way, whether it occurs in a republican democracy, purportedly on a ‘non-arbitrary’ basis, or under a dictatorial, arbitrary regime. But the basis on which Hobbes maintained those two propositions was very different from any that successors would have found plausible. This article explores the idiosyncratic principles that led Hobbes to develop his influential point of view. Key Words: freedom • Hobbes • liberalism • libertarianism • liberty.