_Constitution of the Mind._--That such is the constitution of the mind, such the law of its action, admits of no reasonable doubt. No sooner is an event or phenomenon observed, than we conclude, at once, that it is an effect, and begin to inquire the cause. We cannot, by any effort of conception, persuade ourselves that there is absolutely no cause. _Not derived from Sense._--But is not this principle of causality derived from experience? We have already said that sense does not give it. I do not see with the eye the cause of the melting of the wax, much less does what I see contain the general principle, that _every_ event must have a cause. Sense does not give me this. _Whether from Consciousness._--Still, may it not be a matter of experience in another way, given by _consciousness_, though not by _sense_. For example, I am conscious of certain volitions. These volitions are accompanied with certain muscular movements, and these, again, are followed by certain sensible effects upon surrounding objects. These changes produced on objects without are directly connected thus with my own mental states and changes, with the volitions of which I am directly conscious. Given, the volition on my part, with the corresponding muscular effort, and the external change is produced. I never observe it taking place without such preceding volition. I learn to regard my will as the _cause_, and the external change as the _effect_. I observe that it is in the power of others to produce changes in like manner. Thus I obtain the general idea of cause. It is given by consciousness and experience. _Notion of Causality not thus derived._--It is to this source that a very able and ingenious French philosopher would attribute our first idea of cause. I refer to Maine de Biran. I should agree with M. de Biran, that consciousness of our own voluntary efforts, and of the effects thus produced, may give us our first notion of cause. But it does not give us the law of causality. It extends to a given instance only, explains that, explains nothing further than that, cannot go beyond. I am conscious that in this given instance I have set in operation a train of antecedents and sequences which results in the given effect. I am not conscious that _every_ event has, in like manner, a cause. My experience warrants no such assumption. No induction of facts and cases can possibly amount to this. Induction can multiply and generalize, but cannot stamp on that which is merely empirical and contingent, the character of universality and necessity. The law of causality, in a word, is to be distinguished from any given instance, or number of instances, of actually observed causation. The latter fall within the range of consciousness and experience, the former is given, if at all, as a law of the mind, a primary truth, an idea of reason.