great fame, and fortune followed in its wake. In 1757 came his restatement of Book II of the Treatise. In 1763-1765 Hume was secretary of the English Embassy at Paris, and he was made much of by French society. The thought of the French Enlightenment had advanced far enough to entertain him and his doctrines. Hume met Rousseau at this time. Later Hume was visited by Rousseau in England and was badly treated by the eccentric Frenchman. He says that Rousseau sins at the foundation. Hume was appointed UnderSecretary of State in 1766; he returned to Edinburgh in 1769, and died in 1776. Influences upon the Thought of Hume. The writings of Hume show no erudition, and for that reason it is uncertain what were all the sources from which he drew. He does not mention Descartes, for example, although he wrote his Treatise at La Flêche in the shadow of the school where Descartes was educated. It is probable, however, that Hume was influenced at least by the Greek philosophers of the Hellenic-Roman Period, and by Locke. During the years after Hume's student life at the university, he pored over the writings of the Roman Stoics in the library at Ninewells, and he felt the influence of Cicero, Seneca, and Plutarch. Hume read extensively, and he reacted from his reading. He became so dissatisfied with the past that he put it aside, in the belief that the true philosophy had not yet been written. In this reaction from the past he was influenced along the lines of Locke and Berkeley. He admired the advance that Berkeley had made over Locke, and naturally took a further step in the same direction. Hume was also acquainted with the writings of Hobbes and with the history of the English theories of morals. In 1740 he became acquainted with Adam Smith, the political economist, and Hume's Political Discourses (1752) anticipated Smith's classic Wealth of Nations. At this time (1752) he turned with all other Englishmen from the discussion of philosophical to political topics. There are many points of resemblance between Smith and Hume, especially in their ethical doctrine. Dogmatism, Phenomenalism, and Skepticism. Hume liked to speak of himself as a skeptic, but philosophically speaking he was skeptical only of the dogmatic Rationalism of the Renaissance, which had made unlimited claims for the human reason. Hume maintained in the spirit of the Enlightenment that the human mind deals with ideas and not with reality. Human knowledge has therefore its limits. More consistently than Locke or any one else in the Enlightenment, he tried to show the limits and extent of human knowledge. Pure skepticism is the denial that there is any such thing as truth; pure dogmatism would be the deductive explanation of all problems from a set of infallible principles. It would be hard to find an absolutely true example of skepticism or dogmatism, for generally philosophical theories are a mixture of dogmatism and skepticism. Pyrrho is often given as an example of the pure skeptic, but Pyrrho, like all other Greeks, never for a moment doubted the existence of an external, material object (vol. i, chapter xii). Spinoza is a fairly good example of a pure dogmatist, but he developed his Ethics by means of interpolated principles not in his original assumptions. A thorough-going skeptic would have to be a modern-not a Greek-who would deny that truth can be known and that things exist. This was not Hume's contention. He affirmed the validity (1) of mathematical reasoning (2) and of matters of fact, and (3) the probability of the natural sciences. Hume may correctly be called a phenomenalist, a positivist, or an agnostic. So far as he maintained that there are some things which the reason cannot know, he is an agnostic. In his affirmation that we can know ideas and only ideas, he is a positivist. In his affirmation that ideas are the only existences, he is a phenomenalist. Are external objects the cause of sensations? Experience is dumb. Have external objects an existence? Experience is dumb. Are souls the substance of our thoughts? Experience is dumb. But mathematics has truth, experience is beyond question, and the workings of nature are probable. We shall find Hume to be the keenest critical mind of this critical period of the Enlightenment. He is profoundly serious in his examination of the roots of the intellectual life. He is past-master in the art of raising questions. He not only shows that the fundamental theoretical problems are still unsolved, but he also calls to account the hitherto untested assumptions of practical life. But this is criticism, positivism, phenomenalism, or agnosticism, and not skepticism. He speaks of his doctrine as like that of the Middle Academy, in contrast with that of Pyrrho. He says that excessive skepticism upsets activity, employment, and common occupations. The conclusions of the intellect never agree with our natural instincts. Every time positive skepticism appears, nature destroys it. Hume's conclusion as to the practical attitude of the positivist toward life can best be stated in his own words (Treatise, Book I, Conclusion): "Shall we then establish it for a general maxim, that no refined or elaborate reasoning is ever to be received? If we embrace this principle, we run into the most manifest absurdities. If we reject it in favor of those reasonings, we subvert entirely the human understanding. We have, therefore, no choice left, but between a false reason and none at all. Most fortunately it happens that since reason is incapable of dispelling these clouds, nature suffices to that purpose, and cures me of this philosophical melancholy. I dine, I play a game of backgammon, I converse, and am merry with my friends. —No: If I must be a fool, as all who reason or believe anything certainly are, my follies shall at least be natural and agreeable. In all the incidents of life we ought still to preserve our skepticism. Where reason is lively and mixes itself with some propensity it ought to be assented to." The Origin of Ideas. Locke did not proceed to the construction of his theory of knowledge until he had disclaimed at length his belief in the existence of innate ideas. Berkeley went further and made his polemic against the existence of all abstract ideas, Hume went still further and denied that any ideas existed except those derived from impressions. Locke's attack upon innate ideas was an attack upon unverified tradition; Berkeley's attack upon abstract ideas was an attack upon materialism; Hume made a general attack upon rationalism. The psychology of Hume is thus made simple. It is a cancellation of the factors incompatible with strict empiricism-the factors which he found in Locke and Berkeley. Hume's empirical psychology is simply this: every idea is the image or copy of an impression. What is an impression? Impressions are of two classes: (1) sensations or outer impressions; (2) feelings or emotions or inner impressions. Impressions are never mistaken, because they always have a very lively and vivid character. What is an idea? It is the copy of an impression. An idea should never be mistaken for an impression, because it is fainter and more feeble than the impression of which it is the copy. For example, the sensation of yellow is more vigorous than the thought of yellow; the feeling of anger more vivid than the thought of anger. Impressions are simple and elemental. Can we go back of them and find their origin? We cannot. We receive impressions; echoes of impressions linger as ideas; ideas may be compounded with other ideas. Hume deals in his criticism mostly with the compounding or combining of ideas, but this is the sum and substance of his psychological analysis of our mental life. The following table will help us. [ Sensations or outer impres Impressions sions (=original) Feelings or inner impres Ideas sions Memories or an exact re production of an impres sion or of a combination of impressions (derived) Imagination or a combina tion, separation, and transposition of impressions according to the imagination's own laws. It should be noted, however, that the above classes are not coördinate according to Hume. Impressions are |