The simple facts of consciousness are facts of sense, but not of common sense; the mind feels them when it abstracts objectiveness and generality; what it experiences within itself is an experience exclusively its own, and one which has no connection with others. The word _common_ shows the objects of this criterion to be common to all men, and consequently referable to the objective order, since the purely subjective, as such, is limited to the individual, and in no wise affects what is general. So exact is this observation, that in ordinary language no internal phenomenon, however extravagant, is ever said to be opposed to common sense, provided it be expressed simply with abstraction from its relation to the object. If a man says: I experience such or such a sensation, I seem to see such or such a thing, common sense is not against him; but if he says, such or such a thing is in such a manner, and the assertion is extravagant, it is against him, for this is contrary to common sense. 316. I believe the expression _common sense_ to denote a law of our mind, apparently differing according to the different cases to which it applies, but in reality and apart from its modifications, only one, always the same, consisting in a natural inclination of our mind to give its assent to some truths not attested by consciousness nor demonstrated by reason, necessary to all men in order to satisfy the wants of sensitive, intellectual, and moral life. If the fact be agreed on, the name is of little moment: whether _common sense_ be or be not the most adequate to signify it, is a philological, not a philosophical, question. What we have to do, is to inquire if this inclination of which we have spoken, really exists, under what forms it is presented, to what cases it is applicable, and how far, and to what degree it may be considered a criterion of truth. Evidently this inclination cannot, in the complication of the acts and faculties of our soul, and in the multitude and diversity of the objects offered to it, always be presented with the same character; it must undergo various modifications capable of causing it to be considered as a distinct fact, although in reality still the same, transformed in a suitable manner. The best means of avoiding a confusion of ideas, will be to designate the various cases in which the exercise of this inclination occurs. 317. We at once detect it in the case of truths immediately evident. The understanding neither does nor can prove them, and yet it must assent to them, or perish like a flame that has nothing to feed upon. The possession of one or more of these primitive truths is an indispensable condition to intellectual life; without them intelligence is an absurdity. Here, then, we find all that is comprised in the definition of common sense: the impossibility of proof; an intellectual necessity, which must be satisfied by assent; and an irresistible and universal inclination to give this assent.