Wherefore, all propositions concerning future things, contingent or not contingent, as this, it will rain tomorrow, or this, tomorrow the sun will rise, are either necessarily true, or necessarily false; but we call them contingent, because we do not yet know whether they be true or false; whereas their verity depends not upon our knowledge, but upon the foregoing of their causes. But there are some, who though they confess this whole proposition, tomorrow it will either rain, or not rain, to be true, yet they will not acknowledge the parts of it, as, tomorrow it will rain, or, tomorrow it will not rain, to be either of them true by itself; because they say neither this nor that is true determinately. But what is this determinately true, but true upon our knowledge, or evidently true? And therefore they say no more but that it is not yet known whether it be true or no; but they say it more obscurely, and darken the evidence of the truth with the same words, with which they endeavour to hide their own ignorance.
Active power consists in motion.
6. In the 9th article of the preceding chapter, I have shewn that the efficient cause of all motion and mutation consists in the motion of the agent, or agents; and in the first article of this chapter, that the power of the agent is the same thing with the efficient cause. From whence it may be understood, that all active power consists in motion also; and that power is not a certain accident, which differs from all acts, but is, indeed, an act, namely, motion, which is therefore called power, because another act shall be produced by it afterwards. For example, if of three bodies the first put forward the second, and this the third, the motion of the second, in respect of the first which produceth it, is the act of the second body; but, in respect of the third, it is the active power of the same second body.
Cause, formal and final, what they are.
7. The writers of metaphysics reckon up two other causes besides the efficient and material, namely, the ESSENCE, which some call the formal cause, and the END, or final cause; both which are nevertheless efficient causes. For when it is said the essence of a thing is the cause thereof, as to be rational is the cause of man, it is not intelligible; for it is all one, as if it were said, to be a man is the cause of man; which is not well said. And yet the knowledge of the essence of anything, is the cause of the knowledge of the thing itself; for, if I first know that a thing is rational, I know from thence, that the same is man; but this is no other than an efficient cause. A final cause has no place but in such things as have sense and will; and this also I shall prove hereafter to be an efficient cause.
CHAPTER XI.
OF IDENTITY AND DIFFERENCE.
[1.] What it is for one thing to differ from another.—[2.] To differ in number, magnitude, species, and genus, what.—[3.] What is relation, proportion, and relatives.—[4.] Proportionals, what.—[5.] The proportion of magnitudes to one another, wherein it consists.—[6.] Relation is no new accident, but one of those that were in the relative before the relation or comparison was made. Also the causes of accidents in the correlatives, are the cause of relation.—[7.] Of the beginning of individuation.
What it is for one thing to differ from another.
1. Hitherto I have spoken of body simply, and accidents common to all bodies, as magnitude, motion, rest, action, passion, power, possible, &c.; and I should now descend to those accidents by which one body is distinguished from another, but that it is first to be declared what it is to be distinct and not distinct, namely, what are the SAME and DIFFERENT; for this also is common to all bodies, that they may be distinguished and differenced from one another. Now, two bodies are said to differ from one another, when something may be said of one of them, which cannot be said of the other at the same time.