It is plausible to think that before the emergence of terms like “consciousness” and “Bewusstsein,” philosophers and scientists relied on intuitions about phenomena of subjective experience that we would now classify as “conscious.” In other words, pre-modern thinkers availed themselves of one or another concept of consciousness as they developed their theories of mind, perception, representation, the self, etc., although they did not attend to consciousness in its own right. In the early modern period, terminology of consciousness emerges to pick (...) out concept(s) of consciousness. This brings with it an occasion for philosophical disagreements concerning consciousness among contemporaries, on the one hand, and an occasion for us as interpreters of historical authors to better assess their views on consciousness, on the other. (shrink)

Leibniz's principle of sufficient reason (PSR) is the claim that everything has a sufficient reason. But is Leibniz committed to the necessity or to the contingency of his great principle? I argue that Leibniz is committed to its contingency, given that he allows for the absolute possibility of entities that he claims violate the PSR. These are all cases of qualitatively indiscernible entities, such as indiscernible atoms, vacua, and bodies. However, Leibniz's commitment to the contingency of the PSR seems to (...) stand in tension with his inference of the PSR from his theory of truth. I argue that this apparent tension can be resolved satisfactorily. When it comes to his modal views on the PSR, Leibniz's position is entirely consistent. (shrink)

I argue that Leibniz's rejection of the hypothesis of thinking matter on grounds of unintelligibility conflicts with his position on sensible qualities such as color. In the former case, he argues that thought must be a modification of something immaterial because we cannot explain thought in mechanical terms. In the latter case, however, he (rightly) grants that we cannot explain sensible qualities in mechanical terms, that is, cannot explain why a certain complex mechanical quality gives rise to the appearance of (...) a certain sensible quality, even while insisting that sensible qualities are modifications of bodies. I argue that the two cases are analogous in the relevant respects, and that Leibniz's (plausible) position on sensible qualities should have thrown his Principle of Intelligibility into doubt. (shrink)

Early modern debates about the nature of matter interacted with debates about whether matter could think. In particular, some philosophers (e.g., Cudworth and Leibniz) objected to materialism about the human mind on the grounds that matter is passive, thinking things are active, and one cannot make an active thing out of passive material. This paper begins by looking at two seventeenth-century materialist views (Hobbes’s, and one suggested but not endorsed by Locke) before considering that objection (which I call here the (...) Activity Argument). In discussion, I note that several philosophers of the time believed that matter was active. That view opens up a possible response to the Activity Argument. The paper concludes by looking at the views of two materialists of the time who also believed that matter was active, Toland and Cavendish. (shrink)

Section 17 of Leibniz’s Monadology contains a famous argument in which considerations of what it would be like to enter a machine that was as large as a mill are offered as reasons to reject materialism about the mental. In this paper, I provide a critical discussion of Leibniz’s mill argument, but, unlike most treatments, my discussion will focus on texts other than the Monadology in which considerations of the mill also appear. I provide a survey of three previous interpretations (...) of the argument and a partial defence of one of them, namely the one that Marc Bobro and I offered in Stepping Back Insider Leibniz's Mill (The Monist, 1998). However, I also argue that a fourth interpretation is necessary to account for the appearances of Leibniz’s mill in at least some of his writings. (shrink)

We propose a new theory to explain the nature and function of subjective experience, as a mechanism that guides the organism towards beneficial outcomes. In simple animals, that guidance takes the form of an affect producing a fitness-enhancing response. In human consciousness, there is not a single response, but a range of potential developments allowing a free choice. That range can be modelled as a local prospect: a field of possibilities centred on the present situation and coloured by valence. Building (...) on neural models of global workspace and adaptive resonance, we suggest how such a prospect could be implemented in the brain: as a halo of activation diffusing from, and feeding back into, a core of circulating activation. Using the thought experiment of qualia inversion, we argue that local prospect theory solves the ‘hard problem of consciousness’. We show how our theory explains key characteristics of consciousness: subjectivity, feeling, free will, agency, transience, continuity, integration, selectivity, intentionality, and ‘what it is like’. (shrink)