We divide the whole of the work into six parts : the first whereof gives the substance, or general description of the knowledge which mankind at present possess; choosing to dwell a little upon things already received that we may the easier perfect the old, and lead on to new; being equally inclined to cultivate the discoveries of antiquity, as to strike out fresh paths of science.  In classing the sciences we comprehend not only the things already invented and known, but also those omitted and wanted; for the intellectual globe, as well as the terrestrial, has both its frosts and deserts;  It is therefore no wonder if we sometimes depart from the common divisions. For an addition, whilst it alters the whole, must necessarily alter the parts, and their sections; whereas the received divisions are only fitted to the received sum of the sciences, as it now stands.  With regard to the things we shall note as defective; it will be our method to give more than the bare titles, or short heads of what we desire to have done; with particular care, where the dignity or difficulty of the subject requires it, either to lay down the rules for effecting the work, or make an attempt of our own, by way of example, or pattern, of the whole.  For it concerns our own character, no less than the advantage of others, to know that a mere capricious idea has not presented the subject to our mind, and that all we desire and aim at is a wish.  For our designs are within the power of all to compass, and we ourselves have certain and evident demonstrations of their utility.   We come not hither, as augurs, to measure out regions in our mind by divination, but like generals, to invade them for conquest. And this is the first part of the work.
        When we have gone through the ancient arts, we shall prepare the human understanding for pressing on beyond them. The second object of the work embraces the doctrine of a more perfect use of reason, and the true helps of the intellectual faculties, so as to raise and enlarge the powers of the mind; and, as far as the condition of humanity allows, to fit it to conquer the difficulties and obscurities of nature.  The thing we mean, is a kind of logic, by us called The art of interpreting Nature; as differing widely from the common logic, which, however, pretends to assist and direct the understanding and in that they agree: but the difference betwixt them consists in three things, viz., the end, the order of demonstrating, and the grounds of inquiry.
 The end of our new logic is to find, not arguments, but arts; not what agrees with principles, but principles themselves; not probable reasons, but plans and designs of works–a different intention producing a different effect. In one the adversary is conquered by dispute, and in the other nature by works. The nature and order of the demonstrations agree with this object.  For in common logic, almost our whole labour is spent upon the syllogism. Logicians hitherto appear scarcely to have noticed induction, passing it over with some slight comment.  But we reject the syllogistic method as being too confused, and allowing nature to escape out of our hands. For though nobody can doubt that those things which agree with the middle term agree with each other, nevertheless, there is this source of error; that a syllogism consists of propositions, propositions of words, and words are but the token and signs of things.  Now, if the  first notions, which are, as it were, the soul of words, and the basis of every philosophical fabric, are hastily abstracted from things, anti vague and not clearly defined and limited, the whole structure falls to the ground.  We therefore reject the syllogism, and that not only as regards first principles, to which logicians do not apply them, but also with respect to intermediate propositions, which the syllogism contrives to manage in such a way as to render barren in effect, unfit for practice, and clearly unsuited to the active branch of the sciences. Nevertheless, we would leave to the syllogism, and such celebrated and applauded demonstrations, their jurisdiction over popular and speculative acts; while, in everything relating to the nature of  things, we  make use of induction for both our major and minor propositions; for we consider induction as that form of demonstration which closes in upon nature and presses on, and, as it were, mixes itself with action.   Whence the common order of demonstrating is absolutely inverted; for instead of flying immediately from the senses, and particulars, to generals, as to certain fixed poles, about which disputes always turn, and deriving others from these by intermediates, in a short, indeed, but precipitate manner, fit for controversy, but unfit to close with nature; we continually raise up propositions by degrees, and in the last place, come to the most general axioms, which are not notional, but well defined, and what nature allows of, as entering into the very essence of things.
       But the more difficult part of our task consists in the form of induction, and the judgment to be made by it; for that form of the logicians which proceeds by simple enumeration, is a childish thing, concludes unsafely, lies open to contradictory instances, and regards only common matters; yet determines nothing: whilst the sciences require such a form of induction, as can separate, adjust, and verify experience, and come to a necessary determination by proper exclusions and rejections.
       Nor is this all; for we likewise lay the foundations of the sciences stronger and closer, and begin our inquiries deeper than men have hitherto done, bringing those things to the test which the common logic has taken upon trust. The logicians borrow tile principles of the sciences from the sciences themselves, venerate the first notions of' the mind, and acquiesce in the immediate informations of the senses, when rightly disposed; but me judge, that a real logic should enter every province of the sciences with a greater authority than their own principles can give; and that such supposed principles should be examined, till they become absolutely clear and certain. As for first notions of the mind, we suspect all  those that the understanding, left to itself, procures; nor ever allow them till approved and authorized by a second judgment. And with respect to the informations of the senses, we have many ways of examining them; for the senses are fallacious, though they discover their own errors; but these lie near, whilst the means  of discovery are remote.
       The senses are faulty in two respects, as they either fail or deceive us. For there are many things that escape the senses, though ever so rightly disposed; as by the subtilty of the whole body, or the minuteness of its parts; the distance of place; the slowness or velocity of motion; the commonness of the object, &c. Neither do the senses, when they lay hold of a thing, retain it strongly; for evidence, and the informations of sense, are in proportion to a man, and not in proportion to the universe. And it is a grand error to assert that sense is the measure of things.
         To remedy this, we have from all quarters brought together, and fitted helps for the senses; and that rather by experiments than by instruments; apt experiments being much more subtile than the senses themselves, though assisted with the most finished instruments. We, therefore, lay no great stress upon the immediate and natural perceptions of the senses, but desire the senses to judge only of experiments, and experiments to judge of things: on which foundation, we hope to be patrons of the senses, and interpreters of their oracles.  And thus we mean to procure the things relating to the light of nature, and the setting it up in the mind; which might well suffice, if the mind were as white paper. But since the minds of men are so strangely disposed, as not to receive the true images of things, it is necessary also that a remedy be found for this evil.
         The idols, or false notions, which possess the mind, are either acquired or innate. The acquired arise either from the opinions or sects of philosophers, or from preposterous laws of demonstration; but the innate cleave to the nature of the understanding, which is found much more prone to error than the senses. For however men may amuse themselves, and admire, or almost adore the mind, it is certain, that like an irregular glass, it alters the rays of things, by its figure, and different intersections.
         The two former kinds of idols may be extirpated, though with difficulty; but this third is insuperable.  All that can be done, is to point them out, and mark, and convict that treacherous faculty of the mind; lest when the ancient errors are destroyed, new ones should sprout out from the rankness of the soil: and, on the other hand, to establish this for ever, that the understanding can make no judgment but by induction, and the just form thereof.  Whence the doctrine of purging the understanding requires three kinds of confutations, to fit it for the investigation of truth; viz., the confutation of philosophies, the confutation of demonstrations and the confutation of the natural reason. But when these have been completed, and it has been clearly seen what results are to be expected from the nature of things, and the nature of the human mind, we shall have then furnished a nuptial couch for the mind and the universe, the divine goodness being our bridemaid.  And let it be the prayer of our Epithalamium, that assistance to man may spring from this union, and a race of discoveries, which will contribute to his wants and vanquish his miseries. And this is the second part of the work.
         But as we propose not only to pave and show the way, but also to tread in it ourselves, we shall next exhibit the phenomena of the universe; that is, such experience of all kinds, and such a natural history, as may afford a foundation to philosophy.  For as no fine method of demonstration, or form of explaining nature, can preserve the mind from error, and support it from falling; so neither can it hence receive any matter of science. Those, therefore, who determine not to conjecture and guess, but to find out and know; not to invent fables and romances of worlds, but to look into, and dissect the nature of this real world, must consult only things themselves. Nor can any force of genius, thought, or argument, be substituted for this labour, search, and inspection; not even though all the wits of men were united: this, therefore, must either be had, or the business be deserted for ever.
         But the conduct of mankind has hitherto been such, that it is no wonder nature has not opened herself to them.  For the information of the senses is treacherous and deceitful; observation careless,  irregular, and accidental;  tradition idle,  rumorous,  and  vain;  practice  narrow and servile; experience blind, stupid, vague, and broken; and natural history extremely light and empty: wretched materials for the understanding to fashion into philosophy and the sciences! Then comes in a preposterous subtilty of argumentation and sifting, as a last remedy, that mends not the matter one jot, nor separates the errors. Whence there are absolutely no hopes of enlarging and promoting the sciences, without rebuilding them.
         The first materials for this purpose must be taken from a new kind of natural history. The understanding must also have fit subjects to work upon, as well as real helps to work with. But our history, no less than our logic, differs from the common in many respects; particularly, 1. In its end, or office; 2. Its collection, 3. Its subtilty; 4. Its choice; and 5. Its appointment for what is to follow.
         Our natural history is not designed so much to please by its variety, or benefit by gainful experiments, as to afford light to the discovery of causes, and hold out the breasts to philosophy; for though we principally regard works, and the active parts of the sciences, yet we wait for the   time of harvest, and would not reap the blade for the ear. We are well aware that axioms, rightly framed, will draw after them whole sheaves of works: but for that untimely and childish desire of seeing fruits of new works before the season, we absolutely condemn and reject it, as the golden apple that hinders the progress.
         With regard to its collection; we propose to show nature not only in a free state, as in the history of meteors, minerals, plants, and animals; but more particularly as she is bound, and tortured, pressed, formed, and turned out of her course by art and human industry. Hence we would set down all opposite experiments of the mechanic and liberal arts, with many others not yet formed into arts; for the nature of things is better discovered by the torturings of art, than when they are left to themselves.  Nor is it only a history of bodies that we would give; but also of' their cardinal virtues, or fundamental qualities; as density, rarity, heat, cold, &c., which should be comprised in particular histories.
         The kind of experiments to be procured for our history are much more subtile and simple than the common; abundance of them must be recovered from darkness, and are such as no one would have inquired after, that was not led by constant and certain tract to the discovery of causes; as being in themselves of no great use, and consequently not sought for their own sake, but with regard to works: like the letters of the alphabet with regard to discourse.
         In the choice of our narratives and experiments we hope to have shown more care than the other writers of natural history; as receiving nothing but upon ocular demonstration, or the strictest scrutiny of examination; and not heightening what is delivered to increase its miraculousness, but thoroughly purging it of superstition and fable. Besides this, we reject, with a particular mark, all those boasted and received falsehoods, which by a strange neglect have prevailed for so many ages, that they may no longer molest the sciences.  For as the idle tales of nurses do really corrupt the minds of children, we cannot  too carefully guard the infancy of philosophy from all vanity and superstition. And when any new or curious experiment is offered, though it may seem to us certain and well founded; yet we expressly add the manner wherein it was made; that, after it shall be understood how things appear to us, men may beware of any error adhering to them, and search after more infallible proofs. We, likewise, all along interpose our directions, scruples, and c:butions; and religiously guard against phantoms and illusions.
         Lastly, having well observed how far experiments and history distract the mind; and how difficult it is, especially for tender or  prejudiced  persons,  to converse with nature from  the  beginning,  we  shall  continually  subjoin our observations, as so many first glances of natural history at philosophy; and this to give mankind some earnest, that they shall not be kept perpetually floating upon the waves of history; and that when they come to the work of the understanding, and the explanation of nature, they may find all things in greater readiness.  This will conclude the third part.
         After the understanding has been thus aided and fortified, we shall be prepared to enter upon philosophy itself.  But in so difficult a task, there are certain things to be observed, as well for instruction as for present use. The first is to propose examples of inquiry and investigation, according to our own method, in certain subjects of the noblest kind, but greatly differing from each other, that a specimen may be: had of every sort. By these examples we mean not illustrations of rules and precepts, but perfect models, which will exemplify the second part of this work, and represent, as it were, to the eye, the whole progress of the mind, and the continued structure and order of invention, in the most chosen subjects, after the same manner as globes and machines facilitate the more abstruse and subtile demonstrations in mathematics. We assign the fourth part of our work to these examples, which are nothing else than a particular application of the second part of our understanding.
         The fifth part is only temporary, or of use but till the rest are finished; whence we look upon it as interest till the principal be paid; for we do not propose to travel hoodwinked, so as to take no notice of what may occur of use in the way. This part, therefore, will consist; of such things as we have invented, experienced, or added, by the same common use of the understanding that others employ. For as we have greater hopes from our constant conversation with nature, than from our force of genius, the discoveries we shall thus make may serve as inns on the road, for the mind to repose in, during its progress to greater certainties. But this, without being at all disposed to abide by anything that is not discovered,  or proved, by the true form of induction. Nor need any one be shocked at this suspension of the judgment, in a doctrine which does not assert that nothing is knowable; but only that things cannot be known except in a certain order and method : whilst it allows particular degrees of certainty, for tile sake of commodiousness and use, until the mind shall enter on the explanation of' causes. Nor were those schools of philosophers, who held positive truth to be unattainable, inferior to others who dogmatized at will. They did  not, however, like us, prepare helps for the guidance of the senses and understanding, as we have done, but at once abolished all belief and authority, which is a totally different and almost opposite matter.
         The sixth and last part of our work, to which all the rest are subservient, is to lay down that philosophy which shall flow from the just, pure, and strict inquiry hitherto proposed. But to perfect this, is beyond both our abilities and our hopes, yet we shall lay the foundations of it, and recommend the superstructure to posterity. We design no contemptible beginning to the work; and anticipate that the fortune of mankind will lead it to such a termination as is not possible for the present race of men to conceive. The point in view is not only the contemplative happiness, but the whole fortune and affairs, and powers, and works of men. For man being the minister and interpreter of nature, acts and understands so far as he has observed of the order, the works and mind of nature, and can proceed no farther; for no power is able to loose or break the chain of causes, nor is nature to be conquered but by submission: whence those twin intentions, human knowledge and human power, are really coincident; and the greatest hinderance to works is the ignorance of causes.
         The capital precept for the whole undertaking is this, that the eye of the mind be never taken off from things themselves but receive their images truly as they are.  And God forbid that ever we should offer the dreams of fancy for a model of the world; but rather in his kindness vouchsafe to us the means of writing a revelation and true vision of the traces and moulds of the Creator in his creatures.
         May thou, therefore, O Father, who gavest the light of vision as the first fruit of creation, and who hast spread over the fall of man the light of thy understanding as the accomplishment of thy works, guard and direct this work, which, issuing from thy goodness, seeks in return thy glory! When thou hadst surveyed the works which thy hands had wrought, all seemed good in thy sight, and Thou restedst. But when man turned to the works of his hands, he found all vanity and vexation of spirit, and experienced no rest. If, however, we labour in thy works, Thou wilt make us to partake of thy vision and sabbath; we, therefore, humbly beseech Thee to strengthen our purpose, that Thou mayst be willing to endow thy family of mankind with new gifts, through our hands, and the hands of those in whom Thou shalt implant the same spirit.