. 23-27 How are our opinions and convictions to be tested? How are we to know that they are really clear and distinct, and therefore true? By deduction. "Those long chains of reasoning, all simple and easy, which geometers use to arrive at their most difficult demonstrations," said Descartes, "suggested to me that all things which come within human knowledge must follow each other in a similar chain; and that, provided we abstain from admitting anything as true which is not so and that we always preserve in them the order necessary to deduce one from the other, there can be none so remote to which we cannot finally attain, nor so obscure but that we may discover them." 1 Consciousness is the basis of certitude. Deduction is the method of certitude. Those were the two grand theses of Descartes. With their help, regarding his own existence as an unprovable but also an undeniable fact, he proceeded to demonstrate the existence of God, to establish the fundamental difference between soul and body, mind and matter, and then out of these materials to build up the whole universe. Few modern readers can help smiling at the dapper audacity with which he did this; but his exploit was only in logical sequence to the principles from which he started; and to students weary, as was Locke, of Aristotelian and scholastic mystifications, most of his teaching must have been very grateful. The most important of his metaphysical discoveries, or revivals that were equal to discoveries, was his distinction between the primary and secondary qualities of matter.2 1 Discours de la Méthode,' part ii. 2 Illustrated in this extract from the 'Meditationes': "Let us take a piece of wax from the honeycomb. It has some taste and smell; it is hard and His most influential dogma was his theory of innate ideas or necessary truths. "By the word idea," he said, "I understand all that can be in our thoughts; and I distinguish three sorts of ideas ;-adventitious, like the common idea of the sun; framed by the mind, such as that which astronomical reasoning gives of the sun; and innate, as the idea of God, or a triangle, and all others. which represent true, immutable, and eternal essences.' Descartes's dogma of innate ideas, indeed, was the special dogma of his metaphysics, the necessary outcome of his primary axiom, "Cogito, ergo sum," and the battle-ground of the greatest psychological wars that have been waged since his time. This is not the place for any discussion of Descartes's views. Some of them will have to be referred to hereafter, when we are considering Locke's position as a metaphysical teacher and the main points of his divergence from his first master in philosophy, the only guide whom he ever recognised as a master. Here it is only requisite to note, in as concise a way as may be, the sort of influences that that master exerted, or sought to exert, upon him. And in this connection it should be remembered that Descartes, however eminent as a metaphysician, was much besides a metaphysician. He may be regarded as almost the greatest modern cold; it has colour, form, and size. Approach it to the fire: it becomes liquid, warm, inodorous, tasteless; its form and colour are changed; its size is increased. Does the same wax remain after these changes? It must be allowed that it does; no one doubts it; no one thinks otherwise. What was it then that we so distinctly knew to exist in this piece of wax? Nothing certainly that we observed by the senses, since all that the taste, the smell, the sight, the touch reported to us has disappeared, and yet the same wax remains." 1 Lettre liv. mathematician before Newton, his application of algebra to geometrical curves-concerning which, however, he appears to have purloined a good deal from Harriott or older mathematicians-being only one of many excellent services to this branch of science. He was also a great physiologist, "inasmuch," we are told on high authority, "as he did for the physiology of motion and sensation that which Harvey had done for the circulation of the blood, and opened up the road to the mechanical theory of these processes which has been followed up by all his successors."1 And if the truths that he taught were thus useful, the vehemence of intellect that often led him far beyond the limits of known truth was not useless. "Bacon," says Condorcet, "though he possessed in a most eminent degree the genius of philosophy, did not unite with it the genius of the sciences. The methods proposed by him for the investigation of truth, consisting entirely of precepts he was unable to verify, had little or no effect in accelerating the rate of discovery. That honour was reserved for Descartes. If in the physical sciences his march was less sure than that of Galileo, his logic was less cautious than that of Bacon, yet the very temerity of his errors was instrumental to the progress of human thought. He gave activity to minds which the circumspection of his rivals could not awaken from their lethargy. He called upon men to throw off the yoke of authority, and to acknowledge no dogma but what reason sanctioned; and his call was obeyed by a multitude of followers, encouraged by the boldness and fascinated by the enthusiasm of their leader." No slight honour is due to Descartes, in addition to all his other claims to honour, for having set Locke thinking. 1 Professor Huxley in the Fortnightly Review for November, 1874. Of the way in which Locke began to think on philosophical questions two curious little illustrations have come down to us. They occur in a memorandum book belonging to his father, which has already furnished us with much interesting information, and in which are many other entries in Locke's handwriting, evidently made for his father's use or entertainment. As the elder Locke died in February, 1660-1, and the memorandum book then ceased to have any new entries made in it, there can be no doubt that they were written before the close of 1660. They are probably of a much earlier date. "PHILOSOPHY. "It is sorted into three parts, namely, Physic, Ethic and Dialectic. 66 Physic is to discern and judge of the world and of such things as are therein. "Ethic is to treat of life and manners. "Dialectic, that is, Logic, to make reasons to grow, and improve both Physic and also Ethic, which is Moral Philosophy. "Moral Philosophy is the knowledge of precepts of all honest manners which reason acknowledgeth to belong and appertain to man's nature, as the things [in] which we differ from beasts'. It is also necessary for the comely government of man's life. "Necessity was the first finder-out of moral philosophy, and experience (which is a trusty teacher) was the first master thereof. "Socrates is called by Laertius the first beginner thereof, because he taught it more than any of the rest (men must be the beginners of men's matters); notwithstanding the sages amongst the Athenians, as Thales and Solon, both spake and wrote of like matter before him, yet because he so earnestly embraced it, and equally placed it with th' other two sorts of Philosophy, he deserveth well the glory of the first beginner thereof. Plato, disciple of Socrates, in his book of moral wisdom, as well as many other of Plato's works, are full of divinity, as St. Augustine witnesseth. "And therefore, because Socrates was before Jesus Sirach, the beginning thereof is to be referred unto him. As for Solomon's works, they are more divine than moral, and is rather to be worshipped in the divinity than honoured with the beginnings of moral philosophy." "OF THE KINDS OF TEACHING MORAL PHILOSOPHY. "First, by counsels, laws, and precepts, counselling and admonishing men to virtue by precepts, and by laws deterring them from vice. 66 Secondly, by proverbs and adages showing the contraries of things, preferring always the best, thereby declaring both the profit of virtue and inconveniences of vice. "Thirdly, by parables, examples, and semblances, wherein by easy and familiar truths hard things and more out of use are declared, that by the one th' other may be better perceived and borne in mind.” 1 The earliest, or nearly the earliest, of his extant compositions, those notes, short and crude as they are, throw some welcome light on Locke's temper as a young student in philosophy. "Men must be the beginners of men's matters." "Necessity was the first finder-out of moral philosophy, and experience (which is a trusty teacher) was the first master thereof." It would seem that Locke had already broken off, not only from Aristotelianism and scholasticism, but also from Cartesianism; or if, as is more likely, he wrote thus before he read Descartes, that he was prepared to accept from him only such guidance as would help him to become, not a Cartesian, but like Descartes, and with a firmer will and shrewder judgment, though not a keener intellect, a seeker after truth. That Locke seriously set himself to that quest under the leadership of Descartes, while he was an Oxford student, we are positively informed. That he supplemented or joined with his study of Descartes the study of other great writers contemporary with him, or coming a little after him, cannot be doubted. But, without records to support us, we should not be justified in speculating as to the range of his extra-university studies. at this early stage of his life. We only know, from state 1 Additional MSS., no. 28273, in the British Museum. |