Almost a half century after the publication of the Philosophical Investigations, it seems important to ask why Wittgenstein"s ideas have had so little impact on contemporary discussions in the philosophy of mind. A clue can be discerned by what Georges Rey says in the introduction to his book on contemporary philosophy of mind. Rey announces at the outset to his readers that his treatment of the mind aspires to be continuous with science, not with literature. He explains that there is a recent resurgence of interest in the philosophy of mind with "explanatory questionsâ€? about what sort of thing a pain, a thought, a mental image, a desire, or an emotion is. Neither materialism nor dualism provides a "seriousâ€? theory about the mind, which will give us a "seriousâ€? explanation of mental phenomena. According to Rey, although old-style grammatical investigations may have given us a "heightened sensitivity to complexities and nuances of our ordinary mental talk,â€? they "tended to occur at the expense of further theorizing about the mental phenomena themselvesâ€? (Rey, 4).