Part IV, Chapter 7: Of some Axioms which are important
EVERY one allows that it is important to have in the mind many axioms and principles, which, being clear and indubitable, may be employed as a foundation for obtaining a knowledge of things more obscure. But those which are commonly given are of such little use that it is scarcely worth while to know them; for that which is called the first principle of knowledge—it is impossible for the same thing to be, and not to be—is very clear and certain; but I do not see how it can avail to furnish us with any knowledge. I believe, therefore, that those which follow will be of more use. I commence with that which we have already explained.
1st AXIOM.
Everything which is contained in the clear and distinct idea of a thing may be affirmed of it with truth.
2d AXIOM.
Existence (possible at least) is contained in the idea of every thing which we conceive clearly and distinctly.
For as soon as a thing is conceived clearly we cannot but regard it able to be so, since it is only the contradiction which we find between our ideas, which leads us to believe that a thing cannot be. Now there can be no contradiction in an idea when it is clear and distinct.
3d AXIOM.
Nothing cannot be the cause of anything. Other axioms spring from this, which may be called its corollaries; such as the following: —
4th AXIOM, or 1st COROLLARY of the Third.
No thing, nor any perfection of that thing actually existing, can have nothing, or a thing non-existent, as the cause of its existence.
5th AXIOM, or Second COROLLARY of the Third.
All the reality or perfection which is in a thing, is found, formally or eminently, in its first and total cause.
6th AXIOM, or 3d COROLLARY of the Third.
No body is able to move itself,—that is to say, to give itself motion when it has none.
This principle is so evident, naturally, that it caused the introduction of substantial forms, and the real qualities of heaviness and lightness; for philosophers, seeing, on the one hand, that it was impossible for that which was moved to move itself, and being falsely persuaded, on the other, that there was nothing without the stone which pushed it downwards when it fell, felt themselves obliged to distinguish two things in a stone—the matter which received the motion, and the substantial form, aided by the accident of heaviness, which gave it. They did not, however, observe, that thus they either fell into the difficulty which they wished to avoid, if that form was at once material, that is to say, a true matter,—or that, if it was not matter, it must be a substance which is really distinct from it; which it was impossible for them to conceive clearly,—at least, to conceive as a mind, that is, a substance which thinks, which is truly the form of man, and not that of any other body.
7th AXIOM, or 4th COROLLARY of the Third.
No body can move another, unless it is itself moved. For if a body, being at rest, is unable to give itself motion, it is still less able to give it to another body.
8th AXIOM.
We ought not to deny what is clear and evident because we cannot comprehend what is obscure.
Ninth AXIOM.
It belongs to the nature of a finite mind, that it cannot comprehend the infinite.
Tenth AXIOM.
The testimony of one infinitely powerful, infinitely wise, infinitely good, and infinitely truthful, ought to persuade our minds more powerfully than the most convincing reasons.
For we ought to be more assured that he who is infinitely intelligent cannot be deceived, and that he who is infinitely good cannot deceive us, than we are that we are not deceived in things the most clear.
These three last axioms are the ground of faith, of which we shall say something hereafter.
11th AXIOM.
When those facts of which sense may easily judge are attested by a very great number of persons, of different times, different nations, different interests, who affirm that they have personally known them, and who cannot be suspected of having conspired together to support a deception, we ought to consider them as well established and indubitable as though we had seen them with our own eyes.
This is the ground of the greater part of our knowledge, since the things which we know in this way are more numerous by far than those which we know by our own observation.