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246 unaccompany'd with any meaning, instead of that of modification, makes no addition to our knowledge, nor is of any advantage to the doctrine of the immateriality of the soul.

I add in the second place, that if it brings any advantage to that cause, it must bring an equal to the cause of atheism. For do our Theologians pretend to make a monopoly of the word, action, and may not the atheists likewise take possession of it, and affirm that plants, animals, men, &c. are nothing but particular actions of one simple universal substance, which exerts itself from a blind and absolute necessity? This you'll say is utterly absurd. I own 'tis unintelligible; but at the same time assert, according to the principles above-explain'd, that 'tis impossible to discover any absurdity in the supposition, that all the various objects in nature are actions of one simple substance, which absurdity will not be applicable to a like supposition concerning impressions and ideas.

From these hypotheses concerning the substance and local conjunction of our perceptions, we may pass to another, which is more intelligible than the former, and more important than the latter, viz. concerning the cause of our perceptions. Matter and motion, 'tis commonly said in the schools, however vary'd, are still matter and motion, and produce only a difference in the position and situation of objects. Divide a body as often as you please, 'tis still body. Place it in any figure, nothing ever results but figure, or the relation of parts. Move it in any manner, you still find motion or a change of relation. 'Tis absurd to imagine, that motion in a circle, for instance, shou'd be nothing but merely motion in a circle; while motion in another direction, as in an ellipse, shou'd also be a passion or moral reflection: That the shocking of two globular particles shou'd become a sensation of pain, and that the meeting of two triangular ones shou'd afford a pleasure. Now as these different shocks, and variations, and mixtures are the only changes, of which