Res Cogitans is a stimulating and exasperating book. Again and again Vendler makes new breaks through the crusts of meaning-theory, epistemology and Cartesian exegesis; and then, through these breaks, pulls out plums that had rotted off their trees many summers ago. Out of his valuable improvements upon Austin's locutionary taxonomy he rehashes the most romantic things in the Meno and the Meditations. In Chomsky's wake, he effectively assails Skinnerian stimulus-response learning-theory; but then, in Chomsky's wake, he surrenders learning-theory to Skinner, finding a shelter for just a few epistemic pets in a Darwinianized doctrine of racial concept-inheritance that is, pace Chomsky, unfenced even from Book I of Locke's Essay. Vendler's powerful chapter ‘On What One Knows’ blocks for good current attempts to reduce knowing to an élite suburb of believing; yet the book's central concept of Thinking is so glued to the ‘that…’-clause that thinking is, by implication, denied to Beethoven and Capablanca, as well as to us when doing our undoctrinal car-driving, translating, verse-composing and aporia-tackling.