But there is a still more irresistible argument proving to us the absurdity of the supposition of innate principles. Every principle is a proposition:Chapter ither it affirms, or it denies. Every proposition consists in the connection of at least two distinct ideas, which are affirmed to agree or disagree with each other. It is impossible that the proposition can be innate, unless the ideas to which it relates be also innate. A connection where there is nothing to be connected, a proposition where there is neither subject nor conclusion, is the most incoherent of all suppositions. But nothing can be more incontrovertible than that we do not bring pre-established ideas into the world with us.
Let the innate principle be that "virtue is a rule to which we are obliged to conform." Here are three principal and leading ideas, not to mention subordinate ones, which it is necessary to form, before we can so much as understand the proposition. What is virtue? Previously to our forming an idea corresponding to this general term, it seems necessary that we should have observed the several features by which virtue is distinguished, and the several subordinate articles of right conduct, that taken together constitute that mass of practical judgements to which we give the denomination of virtue. These are so far from being innate that the most impartial and laborious enquirers are not yet agreed respecting them. The next idea included in the above proposition is that of a rule or standard, a generical measure with which individuals are to be compared, and their conformity or disagreement with which is to determine their value. Lastly, there is the idea of obligation, its nature and source, the obliger and the sanction, the penalty and the reward.
Who is there in the present state of scientifical improvement that will believe that this vast chain of perceptions and notions is something that we bring into the world with us, a mystical magazine, shut up in the human embryo, whose treasures are to be gradually unfolded as circumstances shall require? Who does not perceive that they are regularly generated in the mind by a series of impressions, and digested and arranged by association and reflection?
But, if we are not endowed with innate principles of judgement, it has nevertheless been supposed by some persons that we might have instincts to action, leading us to the performance of certain useful and necessary functions, independently of any previous reasoning as to the advantage of these functions. These instincts, like the innate principles of judgement we have already examined, are conceived to be original, a separate endowment annexed to our being, and not anything that irresistibly flows from the mere faculty of perception and thought, as acted upon by the circumstances, either of our animal frame, or of the external objects, by which we are affected. They are liable therefore to the same objection as that already urged against innate principles. The system by which they are attempted to be established is a mere appeal to our ignorance, assuming that we are fully acquainted with all the possible operations of known powers, and imposing upon us an unknown power as indispensable to the accounting for certain phenomena. If we were wholly unable to solve these phenomena, it would yet behove us to be extremely cautious in affirming that known principles and causes are inadequate to their solution. If we are able upon strict and mature investigation to trace the greater part of them to their source, this necessarily adds force to the caution here recommended.
An unknown cause is exceptionable, in the first place, inasmuch as to multiply causes is contrary to the experienced operation of scientifical improvement. It is exceptionable, secondly, because its tendency is to break that train of antecedents and consequents of which the history of the universe is composed. It introduces an action apparently extraneous, instead of imputing the nature of what follows to the properties of that which preceded. It bars the progress of enquiry by introducing that which is occult, mysterious and incapable of further investigation. It allows nothing to the future advancement of human knowledge; but represents the limits of what is already known, as the limits of human understanding.
Let us review a few of the most common examples adduced in favour of human instincts, and examine how far they authorize the conclusion that is attempted to be drawn from them: and first, some of those actions which appear to rise in the most instantaneous and irresistible manner.
A certain irritation of the palm of the hand will produce that contraction of the fingers which accompanies the action of grasping. This contraction will at first take place unaccompanied with design, the object will be grasped without any intention to retain it, and let go again without thought or observation. After a certain number of repetitions, the nature of the action will be perceived; it will be performed with a consciousness of its tendency; and even the hand stretched out upon the approach of any object that is desired. Present to the child, thus far instructed, a lighted candle. The sight of it will produce a pleasurable state of the organs of perception. He will probably stretch out his hand to the flame, and will have no apprehension of the pain of burning till he has felt the sensation.
At the age of maturity, the eyelids instantaneously close when any substance from which danger is apprehended is advanced towards them; and this action is so constant as to be with great difficulty prevented by a grown person, though he should explicitly desire it. In infants there is no such propensity;Chapter nd an object may be approached to their organs, however near and however suddenly, without producing this effect. Frowns will be totally indifferent to a child, who has never found them associated with the effects of anger.