Necessarily in matters of art, when we use the term "Ideal," we mean a general ideal, that is to say, an ideal that would be accepted as such by the general body of men and women. From the fact that the sensorial nerves in all persons are alike in form and character, and that they act in the same way under like conditions, it follows that there must be a general agreement as to degrees of beauty, and thus a common conception of the ideal human being. Experience has demonstrated this at all times, both in respect of the general ideal we are now discussing, and of particular ideals involving special types and characters; and so invariable is this experience that the progression towards similar ideals has all the force of law.[36] This general agreement is subject to certain restrictions. The first is in regard to form in which the imagination cannot proceed beyond experience. The component parts of an ideal form cannot include any which are higher in quality than those which have come within the experience of the person compounding the ideal. Secondly, in regard to abstract qualities, the estimation of these depends upon intelligence and education, and the accumulated experience of these things, which we measure in terms of degrees of civilization. Consequently, different interpretations would be placed upon the phrase "the highest conceivable qualities of form and expression," by the various races of mankind. According as the experience was greater, so would the ideal form be higher in type; and as the civilization was more advanced, so would the abstract qualities exhibited be more perfect in character. But among civilized peoples what is, within our understanding, the ultimate form of the ideal, would not change in respect of abstract qualities, and as to form would only vary in comparatively insignificant details with the width of experience.
It is obvious that there can be only one general ideal covering perfection of form and mind, and this being beyond human experience, can only be associated with a spiritual personage, and necessarily with the highest conceivable spiritual personage--the Supreme Being. In its absolute perfection it may be significant of the Supreme Being of any religion of civilized peoples, but not of other spiritual personages to whom such perfection may also be attributed, because absolute power can only be implied in one such personage. This power cannot be indicated in an ideal expression, and hence there is no alternative but to leave the one general ideal to the Supreme Being.