Stephen Yablo

Is Conceivability a Guide to Possibility

Doubts about a maxim like Hume’s have a variety of historical sources. Some date back as far as Descartes’s claim that, since he can conceive himself in a purely mental condition, his essence is only to think. “How does it follow,” Arnauld asks, “from the fact that he is aware of nothing else belonging to his essence, that nothing else does in fact belong to it?” Others are as recent as the discovery by Kripke and Putnam of necessary truths knowable only a posteriori: May 24, 2004 Is Conceivability a Guide to Possibility? S. Yablo

I–Stephen Yablo

The usual charge against Carnap’s internal/external distinction is one of ‘guilt by association with analytic/synthetic’. But it can be freed of this association, to become the distinction between statements made within make-believe games and those made outside them—or, rather, a special case of it with some claim to be called the metaphorical/literal distinction. Not even Quine considers figurative speech committal, so this turns the tables somewhat. To determine our ontological commitments, we have to ferret out all traces of non-literality in our assertions; if there is no sensible project of doing that, there is no sensible project of Quinean ontology.

Cause and essence

Essence and causation are fundamental in metaphysics, but little is said about their relations. Some essential properties are of course causal, as it is essential to footprints to have been caused by feet. But I am interested less in causations role in essence than the reverse: the bearing a things essence has on its causal powers. That essencemight make a causal contribution is hinted already by the counterfactual element in causation; and the hint is confirmed by the explanation essence offers of something otherwise mysterious, namely, how events exactly alike in every ordinary respect, like the boltssuddenly snapping and its snapping per se, manage to disagree in what they cause. Some prior difference must exist between these events to make their causal powers unlike. Paradoxically, though, it can only be in point of a property, suddenness, which both events possess in common. Only by postulating a difference in themanner — essential or accidental — of the propertys possession is the paradox resolved. Next we need an account of causation in which essence plays an explicit determinative role. That account, based on the idea that causes should becommensurate with their effects, is thatx causesy only if nothing essentially poorer would have done, and nothing essentially richer was needed.

The Real Distinction Between Mind and Body

….it [is] wholly irrational to regard as doubtful matters that are perceived clearly and distinctly by the understanding in its purity, on account of mere prejudices of the senses and hypotheses in which there is an element of the unknown. Descartes, Geometrical Exposition of the Meditations

Replies to Comments on If-Thenism

A relatively undemanding claim ’ sometimes implies, to all appearances, a more demanding one c. That is a donkey, in Dretske’s famous example, appears to imply, since zebras cannot be mules, that It is not a cleverly disguised mule. There are eight pawns on each side appears to require the existence of (sixteen) abstract objects. It’s been reported that The Russians possess lurid video of the president-elect, according to information gathered by a former MI6 operative. This implies, if ‘information’ is factive, that The Russians do possess lurid video of the president-elect. c seems in each case to stick its neck out further than ’ did in some direction. There is the appearance of a further claim that cannot be settled just by settling whether ’. What does it mean for c to make a further claim? To call c more demanding just pushes the question back a step. In what does its greater demandingness consist? Perhaps c’s demands are more onerous. But we have to be careful here. More “onerous” demands seem like they might more easily go unmet; but that runs contrary to our assumption that c is implied by ’. Perhaps c just visits its demands on more of the world. Perhaps it invites further questions, even if the answers are predetermined. I suspect there is truth in all these ideas, but our predicament in any case is the same. An article of common sense has been taken hostage by some unhinged philosophical drifter. There are three main styles of response. We may

Carving Content at the Joints

The judgment ‘Line a is parallel to line b’, in symbols: a || b, can be taken as an identity. If we do this, we obtain the concept of direction, and say: ‘The direction of line a is equal to the direction of line b.’ Thus we replace the symbol || by the more generic symbol =, through removing what is specific in the content of the former and dividing it between a and b. We carve up the content in a way different from the original way, and this yields us a new concept. (Frege 1997, 110–11)

Knights, Knaves, Truth, Truthfulness, Grounding, Tethering, Aboutness, and Paradox

Knights always tell the truth; Knaves always lie. Knaves for familiar reasons cannot coherently describe themselves as liars. That would be like Epimenides the Cretan accusing all Cretans of lying. Knights do not *intuitively* run into the same problem. What could prevent a Knight from truly reporting that s/he always tells the truth? Standard theories of truth DO prevent this, however, for such a report is self-referentially ungrounded. Standard theories have a problem, then! We try to fix it.