Frank Jackson

The sentence ‘x is square’ might have had different truth conditions from those it in fact has. It might have had no truth conditions at all. Its having truth conditions and its having the ones it has rest on empirical facts about our use of ‘x is square’. What empirical facts? Any answer that goes into detail is inevitably highly controversial, but we think that there is a rough answer that is, by philosophers’ standards, relatively uncontroversial. It goes back to Locke 1689 and beyond, and is best known to contemporary philosophers through the work of Grice 1957 and Lewis 1969. It is that we (usually implicitly) agreed, as a matter of contingent fact, to use ‘x is square’ as a way of conveying our taking it to be the case that x is square.

ONE way t0 defend narrow content is to produce a sentence 0f the form ‘S believes that P’, and show that this sentence is true 0f S if and 0nly if it is true 0f any duplicate from the skin in, any doppclgangcr, of S. N0toriously, this is hard to d0. Twin Earth examples are pervasivc.1 Another way to defend narrow content; is t0 show that Only 2. narrow notion can play thc causal explanatory r01c we require 0f contcnt in 2. properly scicntiicm psychology 0r cognitive science. Notoriously, this is hard t0 d0. The considerations—mcthod010gicaI solipsism, the principle 0f autonomy, 0r what:cvcr—invokcd to show that a broad notion 0f content cannot..

JP argue that expressivists must admit that becoming competent with ethical utterances involves learning to make them only when one believes one has the relevant attitude. For expressivists hold that communicating our attitudes is the function of ethical utterances, in which case sincerity demands that we not utter an ethical sentence unless we believe we have the relevant attitude. So (b) is false, as long as we suppose that this commitment, as reflected in well-entrenched and clear-cut (henceforth, 'robust' abbreviates 'well-entrenched and clear-cut') conventions, means that ethical utterances express one's belief that one has the relevant attitude. This, in turn, means that (a) is false, if we grant that a belief expressed in virtue of such conventions provides the utterance's truth-conditions.

Frank Jackson champions the cause of conceptual analysis as central to philosophical inquiry. In recent years conceptual analysis has been undervalued and widely misunderstood, suggests Jackson. He argues that such analysis is mistakenly clouded in mystery, preventing a whole range of important questions from being productively addressed. He anchors his argument in discussions of specific philosophical issues, starting with the metaphysical doctrine of physicalism and moving on, via free will, meaning, personal identity, motion, and change, to ethics and the philosophy of color. In this way the book not only offers a methodological program for philosophy, but also casts new light on some much-debated problems and their interrelations