For asmuch as  every question in Philosophy is either of the Thing or of the Word, to solution wereof many Canons may be given; hence the first part of Philosophy which compriseth them, may be termed Canonick.
But because,  of the Word nothing more is sought then the use or signification, but of the thing the truth, which is of an abstruse Nature; therefore we will, in the second place, comprehend in a few Canons all that belongs to the use of the words; but in the first place lay down those of truth and its criteries (which in number exceed the other), premising some few notes concerning them.
First the truth is twofold, one of existence, the other of Enunciation or judgement.
Truth of existence is that, whereby every thing which exists in the nature of things is that very thing which it is, and no other. Whence it comes to passe that there is no falsity opposite to this truth (for, Orichalcum, for example, is not false gold, but true Orichalcum) and therefore: it is all one whether we say a thing is existent, or true.
Truth of Enunciation, or judgement, is nothing else but a conformity of an enunciation pronounced by the mouth, or of a judgement made in the mind, with the thing enunciated or judged.
This is that truth to which falshood is opposite; for as  it is true that the thing is so as it is said to be, so is it false that it is not so as it is said to bee.
As for that which they call a future contingent,  those disjunctions which are made of contraries, (or rather those complexions which are made by disjunctive particles) are true; as if we should say,  Either Hermachus will live to morrow, or will not live; but  neither of the parts is in this disjunctive proposition, taken singly, is true; for neither is there any necessity in nature that Hermachus shall live to morrow; nor, on the contrary, that he shall not live.
Moreover, because as the thing whose truth is sought, belongs either to speculation onely, or to action, (the first of which appertains to Physick, the latter to Ethick); we must for this reason have a Criterie, or Instrument of judging, whereby it may be examined, judged, and discerned, in order to both these.
But forasmuch as naturall things affect the Sense or Intellect, and morall things the Appetite or Will; for this reason, Criteries are to be taken from both these.
From the Sense, nothing can be taken more basic than its function, Sensation, which likewise is called sense.
From the Intellect, forasmuch as besides the function which it hath, whilst like the sense it contemplateth the thing, as if it were present and apparent, (whence the perception of a thing appearing, which appeareth to be as well to the intellect, as to the sense, is called a phantasie or appearance); forasmuch, I say, as besides this function, it is proper to the Intellect; to ratiocinate or discourse, there is therefore required a pre-notion or anticipation, by looking upon which, something may be inferred.
Lastly, from the Will or Appetite, whose property it is to pursue or shun something, nothing else can be taken, but the affection or passion it self, and that either allective, as pleasure; or aversive, as pain or grief.
 There are therefore in all, three Criteries; Sense, or sensation; Prenotion, or anticipation; and Affection, or passion. Concerning each of these, some Canons are to be prescribed.
Chap 2. Canons of Sense – The First Criteria 
To begin with the Canons which concern Sense; of these there may be laid down four.
Canon 1 – Sense is Never Deceived, and therefore every sensation, and every perception of an appearance, is true. 
This is proved, first, because  all sense is void of ratiocination, and wholly incapable of reminiscense. For neither being moved by it self, nor by any other, is it able to add or detract any thing; or to joyn or disjoyne by enynciating or concluding, so as thereby it might think any thing, and be mistaken in that thought. The Intellect indeed can do this, but the Sense cannot,  whose property it is onely, to apprehend that which is present, and moveth it; as the sight, colour presented to it; but not to discern, that what is there presented is one thing; what there, another. Now where there is a bare apprehension, not pronouncing any thing, there is no errour or falshood.
Next, because  there is nothing that can refell or convince the Senses of falshood (for neither can sense of a like kind refell sense of a like kind; as, the sight of the right eye the sight of the left, or the sight of Plato the sight of Socrates; and this, by reason of the equality of their credits) or that there is the same reason for both. For a pur-blind man doth not lesse see that which he sees, then Lyncetis seeth that which seeth. Neither can that which is of an unlike kind refell that which is of an unlike kind, as the sight the hearing, and the taste the smelling: because they have different objects, and serve not to give judgment of the same things. Neither can one sensation of the same sense refell another, because there is not any sensation wherewith we are not affected; and to which, whilst we are affected with it, we do not adhere, and assent; as whilst we see a staffe one while streight, out of the water; another time, part under water, crooked, for we cannot by any meanes see it crooked in the former condition, or streight in the latter. Lastly, neither can reason or ratiocination, refell the senses; because all ratiocination depends upon previous senses, and it is necessary the senses first be true, before the reason which is founded on them can be true.
This is confirmed; for as much as sense is the first of the Criteries, to which we may appeal from the rest, but it self is self-evident, and of manifest truth. For  if you say, every sense is deceived, you will want a criterie to determine and make good, even that very saying upon any particular sense; or,  if some one onely, you will entangle your selfe in an intricate dispute, when you shall be demanded, Which sense, how, and when it is deceived, or not deceived? So as the controversie not being determinable, you must necessarily be deprived of all Criterie. Whence may be inferred, that, if any appearance to sense be false, nothing can be perceived, or, (to expresse it in other termes) unlesse all appearances, and bare perceptions of a thing be true, there were no credit, constance, and judgement of truth. For,  they who alledge the contradiction of appearances one with another, can never prove even this contradiction of them, or, that some are true, others false; they cannot prove it by any thing that is apparent, for the question is of things apparent; nor by any thing unapparent, for that which is unapparent, is to be demonstrated by something else that is apparent.
Again, this is confirmed; because, taking away the certainty of the senses, and by that means the genuine knowledge of this, we take away all rule of life and action.  For as in a bulding, if the first rule be amisse, the square untrue, the plummet faulty, all things must necessarily be defective, and awry, and disproportioned: so, must all things in life be praeposterous, and full of trouble and confusion, if that which is to be esteemed, as it were the first rule, square, and plummer, for the discerning things good and bad, done or not to be done, be unsincere or perverse that is, if it want the certainty which is, as it were it’s rectitude. Whence it cometh to passe, that though reason, (for example) cannot explain the cause why things neer at hand are square, but seem round afar off; yet is it better to haesitate and alledge some wrong cause, rather then to overthrow the first faith and foundations, whereon the constancy, and security of life is so grounded, that unlesse you dare credit sense, you will not have any way to shun precipitation, and destruction.
Thirdly,  because the truth of the senses is manifest even from this, in that their functions exist in nature, or really and truly are. For that we see and hear, is, as truly something indeed existing, as out very feeling pain; and there is no differences, (as even now we said) between saying, a thing is existent, and true.
To speak more fully,  As the first affections, pleasure and pain, depend upon some causes which produce them, and are by reason of those causes existent
in nature, (that is, pleasure depends on pleasant things, pain on painfull, and it neither cometh to passe, that, what produceth pleasure is not pleasant, nor that what causeth pain is not painfull, but that which produceth pleasure, must necessarily be pleasant, that which pain, painfull, and offensive to nature) in like manner, as to the affections of the appearances produced in us, whatsoever is the efficient cause of them, is undoubtedly such as make this appearance; and being such, it cannot come to passe, that it can be any other then such as that is conceived to be, which makes this appearance: The same is to be conceived of all the rest in particular, for that which is visible, not onely seems visible, but is such as it seems; and that which is audible, not onely seem audible, but is indeed such; and so of the rest: Wherefore all appearances are true, and conformable to reason.
 Hence it is manifest, that the Phantasies even of those who doat and dream, are, for this reason, conceived to be true, for that they truly and really exist, seeing that they move the faculty, whereas, that which is not, cannot move any thing. So that there is a necessity in nature, that the species of things which are received in the intellect, or imagination, being in this manner, moved, mingled, and disturbed; that such Phantasies cannot but be, whatsoever opinion followes them, whereby things are judged to be such in themselves: Of which we are to speak next.
Canon 2 – Opinion Follows Upon Sense, and is Superadded to Sensation, and Capable of Truth or Falsehood. 
This is proved, because, when a Tower (for example) appeareth round to the eye, the sense indeed is true, for that it is really affected with the species of roundnesse, which species is truly such, and hath a necessary cause for which it is such, at such a distance: and withall it is not deceived, for it does not affirme that the Tower is such, but onely behaves it selfe passively, receiving the species, and barely reporting that which appeareth to it. But Opinion, or the mind, whose office it is to conceive or judge, in as much as it adds, as it were from it selfe, that, what appeareth to the sense is a Tower, or that, the Tower, really and in it selfe, is round; Opinion, I say, is that which may be true or false.
Whence may be inferred, that  all phantasies (or sensations) whereby Phaenomena’s (things apparent) are perceived, are true; but opinions admit a difference; for some are true, others false, in as much as they are our own judgments superadded to the appearances; and we judge somethings aright, others amisse, by reason that something is added, and imputed to the appearances, or something detracted from them: and generally sense which is incapable of ratiocination charged with falshood.
But some are deceived by the diversity of those appearances, which are derived from the same sensible object, as in a thing visible, (for example) according as the object seemeth to be either of another colour, or of another figure, or some other way changed; for they conceive that of contrary appearances, one must necessarily be true, and the other which is opposite thereto false. Which certainly is very foolish, and proper to such men as consider not the nature of things. For (to continue our instance of things visible) it is not the whole solid, or the whole solidity of the body which we see; but the colour of the solid body. Now of the colour, that which is in a solid body, and appeareth in those things which are seen nigh at hand, is one; that which is without the solid body, as a species, or image flowing from it, and is received into places scituate one beyond another, such as appeareth in those things which are beheld at a great distance, is another. This latter being changed in the intermediate space, and assuming a peculiar figure, exhibits such an appearance as it selfe indeed is.
Whence, neither the sound which is in the brasse that is struck, nor the voice which is in the mouth of him who crieth aloud, is heard, but that sound of voice which lights upon our sense; for the same thing cannot be in two distant subjects. And as no man saith, that he hears falsly, who perceiveth the sound to be but small at distance, because coming nigher, he perceiveth it, as if it were greater; so neither can we say, that the sight is deceived, for that afar off, it seeth a Tower, little and round; neer, great and square; but rather that it is true. For when the sensible object appeareth to it little, and of such a figure, it is in that place little indeed, and of such a figure, the extremities of those images being broke off, whilst they are conveigh’d through the aire, and thereupon coming into the eye in a lesser angle. And again, when it appeareth great and of another figure, there it is great and of another figure, it not being the same in both places; for here the extremities of the images are more entire, and come into the eye in a greater angle; but it is a great mistake to think, that it is the same thing which appeareth to sight, and affecteth the eye, neare and a farre off.
 Neither can we say that the sight is deceived, when we see a shadow in the Sun-shine to move, to follow our foot-steps, and imitate our gestures. For shadow being but air deprived of light; and the earth as we go, being now here, now there, successively deprived of the Sun’s light, and successively recovering that whereof it was deprived; it comes to passe, that the shadow seems to change place, and to follow us: but the eyes are not therefore deceived, it being onely their office to see the light and to see the shadow in whatsoever place it is. But to affirm, that the very light or shadow which is here, is the same, or distinct from that which even now was there; this belongs not to them, but to the mind, whose office it is to determine and judge. So that whatsoever of falsity happens to be here, it is to be attributed to Opinion, not to Sense.
 The same answer may be given to a thousand other objections, as of a ship which seems to stand still, and the land to move; of the starres, which seem to rest; of mountains far a-sunder, which yet seem to be nigh; of boyes, who, having made themselves giddy by turning, think the roof it selfe runs around; of the Sun appearing to be near the mountains, when as so great spaces divide them; of the appearance of a space under water, as large, as from above it to the sky; of a River which to those who passe over it, seemeth to flow back towards the spring; of a Gallery, which seems narrow at the further end; of the Sun, who seems to rise out of the water, and to go down into the water; of Oars, which seem crooked or broken; of Starrs in the night, which seem to glide over the clouds; of things, which by drawing the eye on one side, seem double.
Canon 3 – All Opinion Attested, or not contradicted by the evidence of sense, is true 
Evidence of sense, I here call that kind of sensation, or appearance, which, all things obstructive to judgement being removed, as distance, motion, indisposition of the medium and the like, cannot be contradicted. Whence to this question, Whether a thing be such as it appears, we ought not to give a sudden answer, but to observe  that which I call Ï€Ï‰Ï‚Î¼ÎµÎ½Î¿Î¼ÎµÎ½Î¿Î½ expectable, in regard that we must stay, untill the thing be fully examined and sifted out, according to all the wayes that it can possibly happen.
 Attestation, I call comprehension, mady by evidence, that the thing conceivable, is such as we before conceived it; as, Plato coming towards me, from a far off, I conjecture, and think, as far as I can quesse at such a distance, that it is Plato; but when he drawes nigher, and the distance is taken away, by the evidence of the thing, then, is there made an attestation that it is Plato.
Not-contradiction is said to be the finding out of a thing not manifest, which we suppose, and conceive by reflecting on something manifest or evident; as when I say, there is Vacuum, which indeed is unmanifest, I am induced thereto by something manifest, that is, by motion; for if there were no vacuum, there would be no motion, seeing the body that should be moved, would not have any place to go into; all things being full, and close pack’d together. Whence that which is apparent or manifest doth not contradict that which is unmanifest, since indeed there is motion.
Thus Attestation and Not Contra-diction, is the Criterie, whereby a thing is proved to be true.
Canon 4 – An Opinion, Contradicted or Not Attested by Evidence of Sense, is False 
In which words,  Contradiction is something opposite to Not-attestation, it being the joint destruction of a manifest thing together with another supposed unmanifest; as for instance, Some affirm, there is not Vacuum; but together with this supposition must be subverted a thing manifest, viz: motion. For if there be no Vacuum, Notion likewise cannot bee, as we have already showed.
In like manner, Contradiction is opposed to Attestation; for it is a subversion, whereby it appeareth that the thing conceivable is not such as it was conceived in the opinion; as a man coming towards us from a far off, we at that distance guesse he is Plato, but the distance being taken away, it appeareth to us by evidence that he is not Plato. This is contradiction; for the thing manifest contradicts the preconceived opinion. Thus an Attestation and Not-contradiction is the Critery by which a thing is proved to be true; so contradiction and not-attestation is the Critery by which a thing is evinced to be false, Evidence being the basis and foundation upon which all right opinion of true and false is grounded.
To omit that evidence is sometimes had by one sense, as about some proper sensible; sometimes by many, as when the sensible is common, as magnitude and figure, distance and position, rest and motion and such like, which may be perceaved both by the sight and touch, and become manifest, if not to one sense, at least to the other. Whereupon it sometimes happens, that by reason of severall qualities, severall senses may be summoned, that the evidence which cannot be got by one may be obtaind by the other; as when we cannot discern by sight, whether the bread that is offer’d to us be true or counterfeit, we may summon our Taste, whereby it will evidently appear which of the two it is.
But this I advise, that, after we have exactly considered all, we adhere to those things which are obvious to us: using our senses, either the common about common sensibles, or the proper about the proper. Since we must hold generally to all evidence which is freely presented to us by every criterie but especially by this: and tenaciously Stick to it, as to an infalible principle, lest either the criteries which are established by Evidence be overthrowne, or errour being established as strong as truth, turn all things upsidedown.
I need not repeat or give particular advice what is to be done about the instance alledged of a Tower; which at distance seems round, but neerer, square: for, from what is deduced it is manifest, that before we assert any thing we must expect or pause, and approach nigher and examine, and learn whether the Tower be such when we come at it, as it appeared farr off.
I shall onely give this generall rule. That unlesse (the truth of the senses being preserved after the manner aforesaid) you distinguish that which is opinable or conceivable into that which is expectable or requireth time, before it be asserted what it is, as being not yet duely perceaved, and into that which is present and proposed to us and throughly examined, it will caome to passe, that you will perpetually be disquieted with deceitfull or vaine opinions. But if, when the things opinable are agitated in you mind, you firmly esteem all that is here called expectable as such indeed, and passe not lightly by it, as if that which is false, not having the attestation of any evidence were firm, and allowable; in this case you will behave your selfe as one that is cautious of all ambiguity, and follicitously takes heed to every judgement, which is rightly or falsely passed of an opinable thing.
Of Praenotion or anticipation may be given four Canons.
Canon 1 – All Anticipation or Praenotion which is in the mind depends on the senses, either by Incursion, or Proportion, or Similitude, or Composition 
I mean that the notion (or Idea and form as it were which being anticipated is called praenotion) is begotten in the mind by Incursion (or incidence) when the thing is incurreth into the sense directly and by it selfe, as a man just before your eyes. By Proportion, when the praenotion is amplified or extenuated, but the number, scituation and figure of the parts with a convenient bignesse of each is retaind; as when having seen a man of due magnitude, we from thence form in our mind the species of a Gyant, by amplification; or of a pigmey, by extenuation. By Similitude, when according to a thing first perceaved by the the sense we fancy another like it; as when we imagine a Citty unseen like to some that we have seen. Lastly, by Composition, when we put as it were into one the distinct notions which we have of two or more things, as when we so unite the notions of a horse and a man, as that the notion of a centaure ariseth out of them, but  not without some assistance of ratiocination.
For  by the word Anticipation or praenotion, I understand a comprehension of the minde, or a suitable opinion or understanding fixed in the mind, and as it were a certain memory or monument of that thing which hath often appeared from without (which the mind hath represented in it selfe after some one of the forementioned manners): Such for example is the idea or form and species, reflecting upon which, we say to our selves that thing is Man. For assoon as ever we hear this word Man pronounced, immediately the image of a man is understood according to the anticipation formed in the mind by the foregoing sensations.
Wherefore that thing which is primarily and chiefly meant by and coucht under every word, and so apprehended by the minde, is somthing perspicuous and manifest: for when we enquire after anything or doubt of it or think it or think something; we should not do it, unlesse wee already had a praenotion of that thing; as when we enquire whether that which appeareth a fat off, be a hors or an oxe it is requisite that we should first have seen and know by anticipation the figure of a horse and oxe. Indeed we could not somuch as name any thing, unlesse we first had some image thereof known by Anticipation.
Hence it comes to passe, that, if it be demanded what anything is, we define or describe it in such maner as it is, according to the anticipation thereof which we have in our mind: Neither do we thus only, being demanded, what some singular thing is, as what Plato is; but also, what an universall is, as Man, not this or that, but considered in generall; this is brought to passe according as the mind, having seen many singulars, and set apart their severall differences, formeth and imprinteth in her selfe the anticipation or that which is common to them all, as an universall notion, reflecting upon which we say, Man (for example) is something animate and endued with such a form.
For,  whilst we conceave any thing, either by enunciation or ratiocination, it depends upon something first evident, unto which thing we having regard and referring our thought, infer that thing of which the question is, to be such or not to be such, that is, the same or another, coherent, or not coherent with it. Thus, if we are to prove that this thing which we behold is a man, we so look back upon the praenotion which we have of Man, as that without any stop wee say, Man is something animate and endued with such a form; this that I see, is animate and endued with such a form; therefore this that I see is Man. Or, It is not animate, nor endued with such a forme, therefore it is not Man.
But it is not necessary to confirme all things with exquisite reasons or arguments, and scrupulous forms of reasoning which are cried up by the Dealecticks: for there is this difference betwixt an argument and the conclusion of the reason, and between a slender animadversion and an admonition; that in one, some occult and (as it were) involved things are unfolded and opened; in the other, things ready and open are judged. But where there are such anticipations as ought to be, then what will follow or not follow from them, or what agrees or disagrees with them is perspicuously discerned, & naturally inferred without any artifice or dialectick construction. Wherefore we need only take care that the ancipattion which we have of things be cleare and distinct.
This is the same we said even now, that the anticipations of things from which we inferre something, and thinking upon which we make sumptions or propositions, which are maxims or principles, by which that which is inferred or concluded is conceaved to be demonstrated, be perspicuous and manifest. For,  demonstration is a speich which collectiing by granted sumptions (or propositions) brings to light a truth not manifest before. Thus to demonstrate that there is Vacuum, which is not manifest, supposing the anticipation of vacuum, & the anticipation of a manifest thing (Motion) these sumptions are premised, If there is motion, there is vacuum, but there is motion, and then is inferred, therefore there is also vacuum.
In this place, Motion is taken for the argument, medium, or signe, which properly ought to be a sensible thing: for the sense is that, according to which it is necessary to make a conjecture by ratiocination, ultimately to that which is unmanifest, although such a signe or medium hath not allwayes a necessary connexion with that which is inferred, but is sometimes only contingent, or probable, and might be otherwise.
Of this kind are many from which we argue chiefly in superiour things, those being such, as may be brought to passe not one way only but many, as was hinted formerly.
 Hither also may be referred that which I use to term Î¹ÏƒÎ¿Î½Î¿Î¼Î±Î½, equivalence by which it is inferred, that one of the contraries being, the other also must be; and when I argue thus. If the multitudes of mortalls be so great, that of immortalls is no less; and, if those things which destroy be innumerable, those which preserve ought also to be innumerable.
Against those who deny there is any demonstration may be brought this argument;  Either you understand what demonstration is, or you understand it not; if you understand and have the notion thereof, then there is demonstration: but if you understand it not, Why do you talke of that whereof you have not any knowledge?
 They who take away the credit of the senses, and professe that nothing can be known being in the same rancks, do they not, when they confesse that they know nothing, imply they know not this very thing, Whether any thing can be known? We should not therefore contend against them, that they walk backwards upon their head; Yet if they affirm they do, and I thereupon grant that this is known by them, I have a fair occasion to aske them, How, since before they saw nothing true in the things themselves, they came to understand what was to Know, and what to be Ignorant.
Lastly, concerning affection (or passion,) which is, as I said, pleasure and pain, there may be four  Canons.
Of these we shall speak more largely in the Ethicks. In the mean time, I shall give this generall advertisement concerning Pleasure: Pleasure is desirable of it self, because it is Pleasure; Grief or Pain is alwaies abhorred and avoidable, because it is Pain; whence I conceive, a wise man will have an eye to this exchange or recompence, that he shun pleasure, if it procure a pain greater then it self; and undergo pain, if it produce a greater pleasure. As, for my own part, I should forsake pleasure, and cover pain, either if remorse were annexed to the pleasure; or a lesser pain might be taken instead of a greater.
I Shall add something concerning the use of words, (which I design’d to speak of last) and especially that which concerns discourse; for which, two Canons may seem sufficient, one for the speaker the other for the hearer: They are these,
Above all,  we must know what things the words signifie; that we may have something, reflecting upon which, we may safely discern, whatsoever we either conceive, or seek, or doubt; otherwise, if all things should escape us undetermined, they who would demonstrate any thing to us, will proceed to infinite, and we our selves gain nothing by our discourse, but words and empty sounds. For it is necessary, we have regard to the notion and primary signification of every word, and that we need not any demonstration to understand that thing, in case we can pitch upon any thing, to which we may refer that point, about which our enquiry, doubt, or opinion, are busied.
Hence it is, that the method of enquiring after truth, which is performed by a certain orderly procedure, ought first to prescribe certain rules, by which that affair may be performed, that so the discoursers may agree, what it is concerning which they discourse. So that if any man shall not first agree to this, but hath a mind rather to cavill and trifle in wordish equivocation, he is not to be discoursed with, or still to be prest to explain himself, what ’tis he would be at; for by this means, his jugling will be discover’d, and his cavills will solve themselves; Nor will he be able to intangle his adversary, but rather discover himself a ridiculous sophister.
 Emp. loc. cit.
 Dic. de fato.
 Cic. Acad. 4.
 Cic. de fato. loc. cit.
 Laert. Cic. Acad. 4.
 Quales Epicurus videtur posse instituisse; collected by Gassendus, ne Canonica cenfeatur id nomen baud jure adepta. pag. 157.
 from Laertius and Plutarch adv. Col.
 Sext. Emp.
 Sext. adv. Log. 2.
 Lucret. lib. 4.
 Sext. Emp. adv. log.
 from Laertius.
 Sext. Emp, adv. log. 1.
 Lucret. loc. cit.
 from Sext. Emp.
 Sext. Emp.
 out of Sext. Emp.
 Sext. ibid.
 out of Laert.
 SIDENOTE WITHOUT CONTENT
 Sext. Emp.
 Cic. de nat. 1.
 Sext. Emp.
 Lucret. lib. 4.
 out of Laertius.