Note 229 — Chapter I · (continued 2)

According to the view of Descartes, it was to be ignored, not denied. There is no instance to be found in his works of a denial of the existence of the external world; nor does the passage quoted from him by Mr. Jobert (New System of Philos. vol. ii. pp. 161, 162, Lond. 1849) at all justify the interpretation of that ingenious writer, who confuses certainty in the ordinary sense of the word with certainty in the Cartesian sense. A similar error is made by those who suppose that his ‘Je pense, donc je suis,’ is an enthymeme; and having taken this for granted, they turn on the great philosopher, and accuse him of begging the question! Such critics overlook the difference between a logical process and a psychological one; and therefore they do not see that this famous sentence was the description of a mental fact, and not the statement of a mutilated syllogism. The student of the philosophy of Descartes must always distinguish between these two processes, and remember that each process has an order of proof peculiar to itself; or at all events he must remember that such was the opinion of Descartes. Compare, on the Cartesian enthymeme, Cousin, Hist. de la Philos. I. série, vol. iv. pp. 512, 513, with a note in Kritik der reinen Vernunft, Kant's Werke, vol. ii. pp. 323, 324.