Hobbes and Thinking Matter
Thomas Hobbes, the first great philosopher to write in the English language, published his most influential work Leviathan in 1651. This is most famous for his description of the life of man in the state of nature as "solitary, poore, nasty, brutish and short", and for his advocacy of absolute sovereignty as the only way to ensure a peaceful society. But the most disturbing aspect of Hobbes' philosophy at the time was his materialism, his insistence that everything that exists (including God) is material. He even went so far as to describe Descartes' theory that the mind is an immaterial substance as a contradiction in terms: "When men make a name of two Names, whose significations are contradictory and inconsistent", the result is "but insignificant sounds", "as this name, an incorporeall body, or (which is all one) an incorporeall substance" (Leviathan, chapter 4).
Many contemporaries – perhaps understandably – took Hobbes to be an atheist, and in 1666 Parliament cited his "atheism" as the probable cause of the plague and fire of London! His "Pernicious" books were publicly burned in Oxford in 1683, because of their "Damnable Doctrines ... false, seditious, and impious, and most of them ... also Heretical and Blasphemous ... and destructive of all Government". Hobbes became known as "The Monster of Malmesbury" (after his Wiltshire home town).
In the wake of Leviathan, a host of notable philosophers lined up to refute Hobbes, for example Ward (1656), More (1659), Stillingfleet (1662), Tenison (1670), Cudworth (1678), Glanvill (1682), and Locke (1690). Always the essential argument was the same, namely, that matter by itself could not possibly think, because there is no intelligible connexion between matter and its motions on the one hand, and conscious thought on the other. The two seem so fundamentally different in kind, that it is inconceivable how the one could bring about the other.
This argument was apparently judged decisive by most philosophers of the early modern period, but David Hume highlighted its weakness in his Treatise of Human Nature of 1739. There he argued that no causal relations are genuinely "intelligible", all knowledge of causes comes only from experience, and hence the lack of an intelligible connexion between matter and thought gives no argument whatever for the lack of a causal relation between them. Moreover such experience as we have indicates strongly that the motion of matter can in fact cause thought, for example when our limbs move and we sense accordingly. (For this important argument, see the last seven paragraphs of Treatise 1.4.5, "Of the Immateriality of the Soul".)
For an excellent account of the controversy, see John Yolton's book Thinking Matter (Blackwell, 1984). For an overall background to the philosophy of the time, and Hume's specific contributions, see the Introduction to Peter Millican's edition of Hume's Enquiry Concerning Human Understanding (Oxford World's Classics, 2007).
"The Monster of Malmesbury"