Cause. Upon seeing things change everyday and upon consideration that all such things had a beginning, we acquire the idea of what we call cause and effect . A cause is everything that is by the efficacy of something; and the effect, is everything that is by the efficacy of a cause. Every cause, by virtue of that fact that it produces an effect, may be called efficient: but insofar as there are different ways of producing an effect, we distinguish different sorts of causes. There are physical causes ; moral causes ; and instrumental causes . I call physical causes , all those things that immediately produce their effects by themselves. I call moral causes , those things which produce effects dependent upon physical causes , from which they immediately emanate. Instrumental causes have this in common with moral causes : they do not themselves produce their own effects, but only do so through the intervention of a physical cause . And this is why we give to the former and the latter the name occasional causes . But what distinguishes them from each other is that, if the former are moral causes via the effects that they produce as occasional causes , at least they are physical causes of the effect by which they become occasional causes of another effect. Purely instrumental causes , on the other hand, are endowed with neither force nor activity and remain forever in the sphere of purely occasional causes , like, for example, brute, insensible and inactive matter. It is not the same for minds whose nature is to be active and consequently, to be physical causes . If my soul is nothing but an occasional cause of diverse movements which it has given rise to in the souls of those with whom I am conversing, at the very least it might be considered a physical cause of its particular determinations.

This is now the place to examine how the soul acts on the body. Is the soul a physical cause , or is it but an occasional cause of various movements it impresses upon the body? The opinions of philosophers are divided on this matter. And we can say that with respect to this last question, the latest efforts of philosophy might well tire itself needlessly in attempts to resolve it. The system of pre-established harmony of which M. Leibniz is the author directs us immediately to the difficulty; namely, that it is a shame that this system destroys freedom and that it renders doubtful the existence of the corporeal world. See the article, where we proved one and the other. The ancient system of the real influence of the soul on the body, destroyed by our Descartes and by Père Malebranche his faithful disciple, finds itself honorably reinstated by the powerful defense that English philosophers grant it today. According to this system, God minimized the efficacy that he granted to the soul by locking it up within the confines of an organized body with which he has united it; the soul's power is thus limited to but a little portion of matter, and it enjoys this power within certain restrictions that constitute the laws of the union. This less subtle system, less refined than that of occasional causes , pleases even more minds in that it accords rather well with natural sentiments , which admits in the soul a real efficacy fot moving matter. But this system that we have described here under the sweetened name natural sentiment , is it not rather the effect of prejudice? In fact, this power of a finite mind on matter, this influence that we suppose it exerts on a substance so different and independent from itself, is very obscure. It is undoubtedly more reasonable to attribute to such minds—by virtue of being active substances that possess the power to move and modify themselves—a similar influence on matter, rather than to attribute to matter—a passive being incapable of acting on its own—a real power to act and to modify the mind. But even what I have just observed is an unfortunate inconvenience for this system; it can in this case only be half true. Even if it is able to explain how the body obeys the soul's will via its movements, it does not explain how the soul in turn faithfully obeys the impressions of the body. It provides reasons only for the action, not for the sensation. On this last point we are left with no choice but to turn to occasional causes and the immediate operation of God on the soul. What does it cost us to have recourse to such causes in order to explain the efficacy of the soul's desires? The entire system would be a simpler and better one.

We are told that this system is hardly philosophical because it travels back to the first cause . And without providing natural reasons for the phenomena which embarrass our intellect, it argues that God's will is responsible for all possible outcomes. We are told that this is what the ignorant man will teach us, if he is ever consulted; for who doesn't know that divine will is the first caus e of everything? It is indeed a universal cause ; and yet, it is not this cause that concerns us here. Instead we ask philosophers to discover the particular cause of each effect. There is no objection more disdainful. Would you like the philosopher, said Father Malebranche, to find causes that do not exist? The real use of philosophy is to lead us to God and to show us by the very effects of nature, the necessity of a first cause. When effects are subordinated to each other, and subjected to certain laws, the task of the philosopher is to discover these laws and to travel by degrees to the first principle by following the chain of secondary causes. There is no progress of causes to the infinite. And this is what proves the existence of God, the most important and first truth. The difference between the peasant and the philosopher, both convinced that the will of God is responsible for everything, is that the philosophersees why His will is responsible for everything, which is something the peasant does not see. The philosopher can discern the effects of which this will is the immediate effect, along with the effect that it produces via the intervention of secondary causes and the general laws to which these secondary causes are, in turn, subjected.

There is a second objection, more substantive than the first: we are told that to resort to occasional causes reduces the action of the divine will to a mere game completely unworthy of Him. These causes are at the same time the effect and rule of divine operation; the action that produces them is also subjected to them. So long as this objection persists regarding the laws that regulate the communication of movement between the different parts of matter, we cannot deny their plausibility. In fact, if bodies do not move by their own activity, the laws of movement in Père Malebranche's system will seem nothing more than a game. But this inconvenience will no longer subsist as soon as we apply the system to the union of body and soul. Although the soul does not have a real efficacy on the body, it suffices that it have the power to modify itself, that it be the physical cause of its own will in order to establish this soul as the occasional cause of certain movements of the body. Here, as the the utility of the soul is the goal, the will of the soul is the rule. As this will is a physical cause of its own acts, it is by this very fact distinct from the will of God, and can become a rule and a principle upon which the divine wisdom renders the changes of matter dependent. The will of a created mind, insofar as they are created by this mind, are a shared cause between the will of God and the movements of the body which accounts for the order of these movements and dispenses us from resorting to the immediate will of God as an explanation. And it seems to me that this is the only way to distinguish general wills from particular wills. Both immediately produce effects, but in the former, the will has a relation only to the singular effect it wants to produce, whereas in the latter, we can say that God wanted to produce this effect, only because he wanted another cause of which this effect would be the consequence. It is indeed the efficacious will of God that makes me walk, but he only wishes me to walk as a consequence of what he has wanted once and for all, namely that the movements of my body follows the desires of my soul. My will to walk is a shared cause between the movement of my body and the desires of my soul. I walk by virtue of a general law. My soul is the real cause of the movements of my body, because it is the cause of its own will, to which it pleased the Creator to attach these movements. In this way, corporeal action for all their good and bad consequences are imputed to itself in this way; it is the real cause according to the most common usage of this term. Cause, in ordinary language, signifies a reason by which an effect is distinguished from another effect, and not this general efficacy that flows through all effects. To render men responsible for their actions, it matters little whether they produce them via a natural efficacy or via a physical power that the Creator gave their soul and that moves the body that is united with Him. But it does matter whether these causes are moral or free. It matters a lot that the soul has sovereignty over its own acts, that it is able, according to its whim, to desire or not desire the corporeal movements that necessarily proceed from His will. If we remove all action from bodies, and move the universe via the efficacy of divine wills, then the laws of movement will no longer be a game. But as soon as you reserve a veritable efficacy for minds, a real power to modify themselves, and as soon as you recognize a certain configuration of the matter to which God unites them, the laws of movement thus becomes, via the diverse sensations it excites in them, an occasion to deploy their own activity.

Apart from physical , moral and instrumental causes , we also distinguish other varieties, namely, material causes, formal causes , exemplary causes , final causes . A material cause is the subject on which the agent works or that which is formed by the agent; marble, for instance, is the material cause of a statue. A formal cause is what determines something to be what it is and that distinguishes it from other things. The formal cause combined with the material cause produces the body or the composite. The exemplary cause is the model that the agent proposes and takes as a guide for its action. This model is either extrinsic or intrinsic to the agent. In the first case, it confuses itself with archetypal ideas, see Idea. In the second case, it takes itself for the rich products of nature and for all the exquisite works of Art. See these two articles. As for what concerns final causes, see the next entry.