Sect. I. our Reasoning: For the Mind does upon W occafion compare them together, compound them into complex Ideas, and enlarge, contract, or separate them, as it difcovers theit Circumftances' capable or not. So that all our Knowledg is, in effect, nothing else but the Perception of the Agreement or Difagree ment of our Ideas in a greater or leffer Number, whereinfoever this Agreement or Difagreement may confift. And becaufe this Perception is immediate or mediate, our Knowledg is twofold.

7. Firft, When the Mind, without the Affiftance of any other Idea, immediately perceives the Agreement or Difagreement of two or more Ideas, as that Two and Two is Four, that Red is not Blew; it cannot be call'd Reafon, tho it be the highest Degree of Evidence: For here's no need of Difcourfe or Probation, Self-evidence excluding all manner of Doubt and Darkness. Propofitions fo clear of themselves as to want no Proofs,their Terms being once understood, are commonly known by the Names of Axioms and Maxims. And it is visible that their Number is indefinite, and not confin'd only to two

or

or three abstracted Propofitions made Ch. 2. (as all Axioms are) from the Obfervation of particular Inftances; as, that the Whole is greater than any Part, that Nothing can have no Properties.

8. But, Secondly, when the Mind cannot immediately perceive the Agreement or Difagreement of any Ideas, because they cannot be brought near enough together, and fo compar'd, it applys one or more intermediate Ideas to difcover it: as, when by the fucceffive Application of a Line to two diftant Houses, I find how far they agree or difagree in Length, which I could not effect with my Eye. Thus from the Force of the Air, and the Room it takes up, I know it has Solidity and Extenfion; and that therefore it is as much a Body (tho I cannot fee it) as Wood, or Stone, with which it agrees in the faid Properties. Here Solidity and Extenfion are the Line by which I find Air and Body are equal, or that Air is a Body; because Solidity and Extenfion agree to both. We prove the leaft imaginable Particle of Matter divifible, by fhewing all Bodies to be divifible; becaufe every Particle of Matter is like

Sect. I. wife a Body: and after the like man

ner, is the Mortality of all living Bodies inferr'd from their Divifibility. This Method of Knowledg is properly call'd Reafon or Demonftration, (as the former Self-evidence or Intuition); and it may be defin'd, That Faculty of the Soul which difcovers the Certainty of any thing dubious or obfcure, by comparing it with fomething evidently known.

9. From this Definition it is plain, that the intermediate Idea can be no Proof where its Agreement with both the Ideas of the Question is not evident; and that if more than one Idea be neceffary to make it appear, the fame Evidence is requir'd in each of them. For if the Connection of all the Parts of a Demonftration were not indubitable, we could never be certain of the Inference or Conclufion whereby we join the two Extreams: So tho Self-evidence excludes Reason, yet all Demonftration becomes at length felf-evident. It is yet plainer, that when we have no Notions or Ideas of a thing, we cannot reafon about it at all; and where we have Ideas, if intermediate ones, to fhew their conftant and neceffary Agreement or Dif

agree

be-Ch. 2.

agreement, fail us, we can never go yond Probability. Tho we have an Idea of inhabited, and an Idea of the Moon, yet we have no intermediate Idea to fhew fuch a neceffary Connection between them, as to make us certainly conclude that this Planet is inhabited, however likely it may feem. Now, fince PROBABILITY is not KNOW. LEDG, I banish all HYPOTHESES from my PHILOSOPHY; because if I admit never fo many, yet my Knowledg is not a jot increas'd: for no evident Connection appearing between my Ideas, I may poffibly take the wrong fide of the Queftion to be the right, which is equal to knowing nothing of the Matter. When I have arriv'd at Knowledg, I enjoy all the Satisfaction that attends it; where I have only Probability, there I fufpend my Judgment, or, if it be worth the Pains, I fearch after Certainty.

i.

CHAP.

'Sect. I.

CHA P. III.

of the Means of INFORMATION.

10.

B

UT befides these Properties of Reason which we have explain'd, we are yet moft carefully to diftinguifh in it the Means of Information, from the Ground of Perfwafion: for the Neglect of this eafy diftinction has thrown Men into infinite Miftakes, as I fhall prove before I have done. The Means of Information I call thofe Ways whereby any thing comes barely to our Knowledg, without neceffarily commanding our Affent. By the Ground of Perfwafion, I understand that Rule by which we judg of all Truth, and which irresistibly convinces the Mind. The Means of Information are EXP ERIENCE and AUTHORITY: Experience (as you may fee N° 4.) is either external, which furnishes us with the Ideas of fenfible Objects; or internal, which helps us to the Ideas of the Operations of our own Minds. This is the common Stock of

all