Part of Berkeley's strategy in his attack on materialism in the Three Dialogues Between Hylas and Philonous is to argue that the epistemological distinction between ideas of so-called primary qualities and ideas of secondary qualities, especially as this distinction is found in Locke, is untenable. Both kinds of ideas-those presenting to the mind the quantifiable properties of bodies and those which are just sensations -are equally perceptions in the mind, and there is no reason to believe that one kind represents (...) true properties of independently existing external objects while the other kind does not. (shrink)

A significant feature of John Stuart Mill's moral theory is the introduction of qualitative differences as relevant to the comparative value of pleasures. Despite its significance, Mill presents his doctrine of qualities of pleasures in only a few paragraphs in the second chapter ofUtilitarianism, where he begins the brief discussion by saying:utilitarian writers in general have placed the superiority of mental over bodily pleasures chiefly … in their circumstantial advantages rather than in their intrinsic nature.… [B]ut they might have taken (...) the … higher ground with entire consistency. It is quite compatible with the principle of utility to recognize the fact, that somekindsof pleasure are more desirable and more valuable than others. It would be absurd that while, in estimating all other things, quality is considered as well as quantity, the estimation of pleasures should be supposed to depend on quantity alone (U, II, 4). (shrink)

Berkeley’s Principles is a curious work. The nominal topic is epistemic. The actual topic is ontological. And it is not uncommon to suggest that ‘Berkeley’s system presents us with unique puzzles, particularly at its foundation.’.