43. Are there in the world any cause and effect? This is equivalent to asking whether there is any change in the world. All change involves a transition from not-being to being. The least change is inconceivable without this transition. Whatever is changed is, after changing, in another way than it was before the change; therefore it has this mode of being which it had not before. This mode did not exist before, it exists now; it has passed, therefore, from not-being to being.
44. Even if we were not in relation with the external world, and our mind was confined to internal facts alone, to the consciousness of the me and its modifications, we should know that there is transition from not-being to being, by the testimony of the successive appearance of new perceptions and affections. Within ourselves we experience the ebb and flow of modifications which pass from not-being to being, and from being to not-being.
45. It is clear, from what has been said, that the ideas of cause and effect suppose a real or possible order of contingent beings. If there were only necessary and immutable beings, there could be no causes and effects.
46. I said (Chap. IV.) that the idea of cause contains the idea of being and the idea of relation to the not-being which has passed or passes to being. The idea of cause is not a simple idea; it is composed of these two. The idea of being alone is not sufficient to constitute it; for we may conceive being without conceiving cause. What the idea of cause adds to the idea of being is something distinct from the idea of being, and not contained in it; it may be called causality, power, productive force, activity, or any such term; they all express the relation of one being to realize in another the transition from not-being to being.
47. In the idea of causality is likewise included another simple idea, which, though accompanying the idea of being, must not be confounded with it. If any one should call it a modification of the idea of being, I should have no objection.
48. Whence does the idea of causality arise? The mere intuition of the idea of being does not seem sufficient to produce it. The idea of being is simple, it expresses nothing but being; we can, therefore, find in it no relation to the transition from not-being to being.
49. Does it, perchance, spring from experience? Here we must distinguish between the idea of causality, and the knowledge of the existence of the cause. Experience reveals the succession of beings, that is, their transition from not-being to being, and vice versa. We have already remarked that in the intuition of not-being with relation to being we see the impossibility of a transition, without the mediation of some being which executes it; therefore the certainty of the existence of the cause arises from experience, combined with the intuition of the ideas of being and not-being.
50. If this experience did not exist, we should not know that causality is possible; because in the idea of being, as we possess it, we do not see the idea of force: we might perhaps conceive the force, but we could not know whether any thing in reality corresponds to it. We should thus have the notion of the force, but not the notice of its existence, nor even the certainty of its possibility.
51. But if we examine it well, this want of experience is an impossible supposition; because a limited intelligent being, as uniting intelligence with limitation, feels the succession of its perceptions, and, consequently, experiences within itself the transition from a not-being to being. And as, on the other hand, it perceives its power of combining ideas, it perceives within itself the existence of causality, of a power which produces its reflections.