For this reason, when it happens that there exists only a single word to express a certain conception, and this word, in its usual acceptation, is thoroughly adequate to the conception, the accurate distinction of which from related conceptions is of great importance, we ought not to employ the expression improvidently, or, for the sake of variety and elegance of style, use it as a synonym for other cognate words.It is our duty, on the contrary, carefully to preserve its peculiar signification, as otherwise it easily happens that when the attention of the reader is no longer particularly attracted to the expression, and it is lost amid the multitude of other words of very different import, the thought which it conveyed, and which it alone conveyed, is lost with it.
Plato employed the expression idea in a way that plainly showed he meant by it something which is never derived from the senses, but which far transcends even the conceptions of the understanding (with which Aristotle occupied himself), inasmuch as in experience nothing perfectly corresponding to them could be found.Ideas are, according to him, archetypes of things themselves, and not merely keys to possible experiences, like the categories.In his view they flow from the highest reason, by which they have been imparted to human reason, which, however, exists no longer in its original state, but is obliged with great labour to recall by reminiscence- which is called philosophy- the old but now sadly obscured ideas.I will not here enter upon any literary investigation of the sense which this sublime philosopher attached to this expression.I shall content myself with remarking that it is nothing unusual, in common conversation as well as in written works, by comparing the thoughts which an author has delivered upon a subject, to understand him better than he understood himself inasmuch as he may not have sufficiently determined his conception, and thus have sometimes spoken, nay even thought, in opposition to his own opinions.
Plato perceived very clearly that our faculty of cognition has the feeling of a much higher vocation than that of merely spelling out phenomena according to synthetical unity, for the purpose of being able to read them as experience, and that our reason naturally raises itself to cognitions far too elevated to admit of the possibility of an object given by experience corresponding to them-cognitions which are nevertheless real, and are not mere phantoms of the brain.
This philosopher found his ideas especially in all that is practical,* that is, which rests upon freedom, which in its turn ranks under cognitions that are the peculiar product of reason.He who would derive from experience the conceptions of virtue, who would make (as many have really done) that, which at best can but serve as an imperfectly illustrative example, a model for or the formation of a perfectly adequate idea on the subject, would in fact transform virtue into a nonentity changeable according to time and circumstance and utterly incapable of being employed as a rule.On the contrary, every one is conscious that, when any one is held up to him as a model of virtue, he compares this so-called model with the true original which he possesses in his own mind and values him according to this standard.But this standard is the idea of virtue, in relation to which all possible objects of experience are indeed serviceable as examples- proofs of the practicability in a certain degree of that which the conception of virtue demands- but certainly not as archetypes.That the actions of man will never be in perfect accordance with all the requirements of the pure ideas of reason, does not prove the thought to be chimerical.For only through this idea are all judgements as to moral merit or demerit possible; it consequently lies at the foundation of every approach to moral perfection, however far removed from it the obstacles in human nature-indeterminable as to degree- may keep us.
*He certainly extended the application of his conception to speculative cognitions also, provided they were given pure and completely a priori, nay, even to mathematics, although this science cannot possess an object otherwhere than in Possible experience.Icannot follow him in this, and as little can I follow him in his mystical deduction of these ideas, or in his hypostatization of them; although, in truth, the elevated and exaggerated language which he employed in describing them is quite capable of an interpretation more subdued and more in accordance with fact and the nature of things.
