at all; why food is digested and ejected; humours and juices carried up and down; the heart and the pulse beat; the entrails, like so many workshops, perform every one its own work; and yet all these and many other things are done without sense. But men have not seen clearly enough of what nature the action of sense is; and what kind of body, what length of time, or what repetition of impression is required to produce pleasure or pain. In a word, they do not seem at all to understand the difference between simple perception and sense; nor how far perception may take place without sense. Neither is this a dispute about words merely, but about a matter of great importance. Concerning this doctrine then (being of great use and bearing upon very many things) let a better inquiry be set on foot. For ignorance on this point drove some of the ancient philosophers to suppose that a soul was infused into all bodies without distinction; for they could not conceive how there could be motion at discretion without sense, or sense without a soul.

That no due investigation has been made concerning the Form of Light (especially as men have taken great pains about perspective) may be considered an astonishing piece of negligence. For neither in perspective nor otherwise has any inquiry been made about Light which is of any value. The radiations of it are handled, not the origins. But it is the placing of perspective among the mathematics that has caused this defect, and others of the kind; for thus a premature departure has been made from Physics. Again the manner in which Light and its causes are handled in Physics is somewhat superstitious, as if it were a thing half way between things divine and things natural; insomuch that some of the Platonists have made it older than matter itself; asserting upon a most vain notion that when space was spread forth it was filled first with light, and afterwards with body; whereas the Holy Scriptures distinctly state that there was a dark mass of heaven and earth before light was created. And where the subject is handled physically and according to sense, it comes at once to questions of radiation; so that there is but little physical inquiry extant on the matter. Now men ought to have sunk their speculations for awhile, and inquired what that is which is common to all lucid bodies; in other words, into the Form of Light. For see what an immense difference of body there is

(if they be considered according to their dignity) between the sun and rotten wood, or even the putrified scales of fish? They should also have inquired why some things take fire and throw out light when heated, and others not. Iron, metals, stones, glass, wood, oil, tallow, when they are subjected to fire, either break into flame, or at least become red; but water and air do not acquire any light from the most intense and raging heat, nor cast forth any brightness. And if any one thinks that this is because it is the property of fire to shine, and air and water are entirely hostile to fire, he can never have rowed on the sea on a dark night in hot weather; when he would have seen the drops of water that are struck up by the oars glittering and shining a thing which happens likewise in the boiling seafroth, which they call "sea-lungs." Lastly, what connexion with fire and lighted matter have glowworms and fireflies, and the Indian fly, which lights up a whole room; or the eyes of some animals in the dark; or sugar while it is being scraped or broken; or the sweat of a horse, hard-ridden on a hot night; and the like? Nay, so little is this subject understood, that most people think sparks from flint to be but air in friction. And yet since the air does not take fire with heat, and manifestly conceives light, how happens it that owls and cats and some other animals can see by night? It must needs be (since sight cannot pass without light) that the air has some pure and natural light of its own, which, though very faint and dull, is nevertheless suited to the visual organs of such animals, and enables them to see. But the reason of this error (as of most others) is that men have not from particular instances elicited the Common Forms of natures; which I have laid down as the proper subject of Metaphysic, which is itself a part of Physic, or of the doctrine concerning nature. Wherefore let inquiry be made of the Form and Origins of Light, and in the meantime let it be set down as deficient. And so much for the doctrine concerning the substance of the soul both rational and sensible, with its faculties; and for the appendices of that doctrine.

OF

THE ADVANCEMENT OF LEARNING.

BOOK V.

CHAPTER I.

Division of the Doctrine concerning the Use and Objects of the Faculties of the Human Soul into Logic and Ethic. Division of Logic into the Arts of Discovering, of Judging, of Retaining, and of Transmitting.

THE doctrine concerning the Intellect (most excellent King), and the doctrine concerning the Will of man, are as it were twins by birth. For purity of illumination and freedom of will began and fell together; and nowhere in the universal nature of things is there so intimate a sympathy as between truth and goodness. The more should learned men be ashamed, if in knowledge they be as the winged angels, but in their desires as crawling serpents; carrying about with them minds like a mirror indeed, but a mirror polluted and false.

I come now to the knowledge which respects the use and objects of the faculties of the human soul. It has two parts, and those well known and by general agreement admitted; namely, Logic and Ethic; only Civil Knowledge, which is commonly ranked as a part of Ethic, I have already emancipated and erected into an entire doctrine by itself, the doctrine concerning man congregate, or in society; and in this place I treat only of man segregate. Logic discourses of the Understanding and Reason; Ethic of the Will, Appetite, and Affections: the one produces determinations, the other actions. It is true indeed that the imagination performs the office of an agent or messenger or proctor in both provinces, both the judicial and the ministerial. For sense sends all kinds of images over to

imagination for reason to judge of; and reason again when it has made its judgment and selection, sends them over to imagination before the decree be put in execution. For voluntary motion is ever preceded and incited by imagination; so that imagination is as a common instrument to both,—both reason and will; saving that this Janus of imagination has two different faces; for the face towards reason has the print of truth, and the face towards action has the print of goodness; which nevertheless are faces,

quales decet esse sororum.1

Neither is the imagination simply and only a messenger; but it is either invested with or usurps no small authority in itself, besides the simple duty of the message. For it was well said by Aristotle, "That the mind has over the body that commandment which the lord has over a bondman; but that reason has over the imagination that commandment which a magistrate has over a free citizen," who may come also to rule in his turn. For we see that in matters of faith and religion our imagination raises itself above our reason; not that divine illumination resides in the imagination; its seat being rather in the very citadel of the mind and understanding; but that the divine grace uses the motions of the imagination as an instrument of illumination, just as it uses the motions of the will as an instrument of virtue; which is the reason why religion ever sought access to the mind by similitudes, types, parables, visions, dreams. And again it is no small dominion which imagination holds in persuasions that are wrought by eloquence; for when by arts of speech men's minds are soothed, inflamed, and carried hither and thither, it is all done by stimulating the imagination till it becomes ungovernable, and not only sets reason at nought, but offers violence to it, partly by blinding, partly by incensing it. Nevertheless, I see no cause to alter the former division; for imagination hardly produces sciences; poesy (which in the beginning was referred to imagination) being to be accounted rather as a pleasure or play of wit than a science. And for the power of the imagination in nature, I have just now assigned it to the doctrine concerning the soul. And its relation to rhetoric I think best to refer to that art itself, which I shall handle hereafter.

Ov. Met. ii. 14. : — Such as sisters' faces should be.

2 Arist. Pol. i. 3.

That part of human philosophy which regards Logic is less delightful to the taste and palate of most minds, and seems but a net of subtlety and spinosity. For as it is truly said that "knowledge is the food of the mind," so in their choice and appetite for this food most men are of the taste and stomach of the Israelites in the desert, that would fain have returned to the flesh-pots, and were weary of manna; which though it were celestial, yet seemed less nutritive and comfortable. And in like manner those sciences are (for the most part) best liked which have some infusion of flesh and blood; such as civil history, morality, policy, about which men's affections, praises, fortunes, turn and are occupied. But this same "dry light parches and offends most men's soft and watery natures. But to speak truly of things as they are in worth, rational knowledges are the keys of all other arts. And as the hand is the instrument of instruments, and mind is the form of forms, so these are truly said to be the arts of arts. Neither do they only direct, but likewise confirm and strengthen; even as the habit of shooting not only enables one to take a better aim, but also to draw a stronger bow.

The logical arts are four in number; divided according to the ends at which they aim. For men's labour in rational knowledges is either to invent that which is sought, or to judge that which is invented, or to retain that which is judged, or to deliver over that which is retained. So therefore the Rational Arts must be four; Art of Inquiry or Invention; Art of Examination or Judgment; Art of Custody or Memory; and Art of Elocution or Tradition. Of these I will now speak separately.

CHAP. II.

Division of the Art of Discovery into discovery of Arts and discovery of Arguments: and that the former of these (which is the most important) is wanting. Division of the Art of Discovery of Arts into Learned Experience and the New Organon. Description of Learned Experience.

INVENTION is of two kinds, very different; the one of arts and sciences, and the other of speech and arguments. The