whom he would ever ascribe all high attributes, but for the unfruitfulness of the way-being a philosophy, as his Lordship used to say, only strong for disputation and contention, but barren of the production of works for the benefit of the life of man-in which mind he continued to his dying day."1 On leaving Cambridge he went to Paris, not to study, but in the service of the ambassador. Thus, a mere stripling, Bacon became a man of affairs essentially practical, and it was only the intervals of business that he devoted to the great design formed in his boyhood, and completed so far as it ever was completed, in his retirement and advanced age, the "Instauratio Magna." "Seeing it was manifest to him that the human understanding creates itself much trouble, nor makes an apt and sober use of such aids as are within the command of man, from whence infinite ignorance of things and innumerable disadvantages arise;" his opinion was, "that with all our industry, we should endeavour, if haply that same commerce of mind and of things (than which a greater blessing can hardly be found upon earth, at least, among earthly felicities), might by any means be entirely restored, or if they might at least be brought to terms of nearer correspondence.' The "Instauratio Magna," then, was the restoration of the direct intercourse of the mind with the external world. No longer were we to imagine certain qualities, such as dryness, moisture, coldness, heat, &c., but we were to bring our senses to bear upon the objects of sense. We were to interrogate nature; to taste, to see, to hear, to smell; and out of the result of this exercise of our powers, to form our conclusions, inferences, or inductions. may be said to have brought philosophy down to earth. The ancients had set the example in reference to the heavenly bodies. "They succeeded, because they were observers, and examined carefully the motions which 1 Rawley's Life of Bacon. Bacon 2 Prolegomena to the Instauratio Magna. they treated of. Mathematical reasoning was very skillfully applied; and no men whatever, in the same circumstances, are likely to have performed more than the ancient philosophers. The philosophers, again, who studied the motion of terrestrial bodies, either did not observe at all, or observed so slightly, that they could obtain no accurate knowledge, and, in general, they knew just as much of the facts as to be misled by them." These are the words of Professor Playfair, an excellent judge; and he adds that the ancients, while they observed the heavens, were satisfied with dreaming over the earth. Bacon's task was to rouse men from this dream, and to teach them the true method of investigating the natural world. His success has been so great, that while by his contemporary biographers he was styled the chancellor of learning, by the present age he may be called the chancellor of the laws of physics; for he still presides over the court of last appeal for all questions connected with the investigation of the properties of matter; and it is a presumptive ground for the rejection of any conclusion, that it has not been arrived at according to the principles of the Baconian philosophy. "Man, the servant and interpreter of nature, does and understands so far as he may have observed, respecting the order of nature in things or in his mind; and further he has neither knowledge or power."" This is the first aphorism in Bacon's Novum Organum, or new organ or instrument for the reconstruction and advancement of science. The novelty of it he points out in various passages to consist in requiring man, in his intercourse with nature, to be as a little child, conscious of his ignorance, anxious to be taught, ready to receive instruction from all natural facts. This is in contradiction to what he calls the anticipation of the 1 Dissertation on Physical Science, prefaced to the Encyclopædia Bri tannica. 2 Nov. Org., Aph. 1. mind—the method generally pursued by the ancient philosophers, when speculating about material objects. They began by assuming certain axioms, and from these axioms they deduced what nature must do. They looked within, and found preconceived notions, which they mistook for innate ideas, and in accordance with which they presumed that the operations of nature would be performed. Bacon, on the other hand, bade men look out of themselves, and mould their notions upon the testimony of their senses, and on them alone.1 But he found that this rule, so obvious to us now as the right one for man to obey in his intercourse with nature, was not to be followed without great effort and the removal of many impediments. The obstacles which obstruct man in the simple apprehension of truth, Bacon classifies into four great divisions, under the heads of Idola Tribus, Specus, Fori, et Theatri,which may be rendered: Idola Tribus, the illusions common to the whole race of man, in virtue of the constitution of his mind; Idola Specus, the illusions of a man's own den, bred out of his peculiar nature, habits, and pursuits; Idola Fori, the illusions derived from common talk-the inaccuracy of language producing inaccurate conceptions, and this inaccuracy being inseparable from the talk of the vulgar; lastly, Idola Theatri, the illusions derived from systems invented by the schools--the imaginary or stage world occupying the place of the actual world. The first class "illusions common to the human race"-he divides into seven orders, the most important of which are the illusions which arise from the fact, that "the mind of man is not like a plain mirror which reflects the images of things exactly as they are; but is like a mirror of an 1 But the senses themselves sometimes, as in Astronomy, require correction, and in Aphorism x. 41, Bacon observes, "It is falsely asserted that human sense is the measure of things." uneven surface, which combines its own figure with the figures of the objects it represents ;"-that is, exact observation is in itself a difficulty, from what Bacon calls the unevenness of the mind. When a man thinks he describes what he has seen or felt, he only describes the impression compounded of the external object and his own. internal image, derived from the texture of his mind when a man speaks of a fact, he in general speaks only of his own belief, derived from this impression. Another species of illusions springs from the pre-occupation of the mind with its own images, so that the outer world either does not gain admittance; or the impression made by the senses is so modified by the pre-existing conceptions of the object, as to lose its resemblance to the thing seen, and appear like the thing supposed. A good illustration of this is afforded by the consent of Polonius to the observation of Hamlet about the cloud Hamlet. Do you see yonder cloud that is almost in the shape of a camel? Ham. Methinks it is like a weasel. Pol. It is backed like a weasel. Ham. Or like a whale ? Pol. Very like a whale." In this short dialogue may be found examples of other Idola Tribus; for instance, it illustrates the power of an affirmation-what might be called the advantage of the initiative the mind is apt to acquiesce in a suggestion. "It is more easily moved by affirmatives than negatives." It would not be easy to over-rate the power of suggestion upon minds in a passive condition. It is exhibited in extreme burlesque in the so-called electro-biology, where the patients are first made purely passive, and then images are suggested. Had Hamlet thrown Polonius into this condition, he would not only have seen a cloud like a weasel, or a camel, but he would have seen the camel, and the 1 Nov. Org., Aph. 41. weasel, and the whale. Besides, Polonius, utterly indifferent about the form of the cloud, and in the most uncritical and unscientific mood of mind, was most anxious to please Hamlet at the moment: and he more readily acquiesced in his suggestions. Another of the Idola Tribus, and one of the most important, is that "what a man would most wish to be true, that he most readily believes." For the human understanding does not consist of what Bacon calls Lumen Siccum, dry light, or pure conception; but is composed of a mixture of will and affection. "Hence the rarity of an impartial judgment; for man rejects what is difficult, from impatience of inquiry; what is sober, because it narrows his hopes; the deeper things of nature, from superstition; the light of experience, from arrogance and pride, lest the mind should seem to be occupied with things low and fluctuating; in fine, passion imbues and infects the understanding in innumerable ways, and in such as are sometimes imperceptible." Such are some of the effects of the Idola Tribus-illusions common to all men. The Idola Specus are the illusions to which men are subject in virtue of their peculiar mental constitutions, or their habits and pursuits. Some minds are too much alive to resemblances, and are led by false analogies into premature generalizations; while others have too sharp an eye for differences, and waste the powers of the reason in making endless distinctions. Another of these spectres of the den is the tendency of most men to ride their hobby, whatever it may be. Thus, the chemist can see nothing in the animal economy but a compendious and locomotive laboratory: all vital actions are reduced by him to chemical processes; while, on the other hand, the electrician finds in his electricity a substitute for gravitation, and in galvanism a satisfactory explanation of all the wonders of the animal and vegetable creation. "It were a good caution," observes |