From the antagonism of the two impulsions, and from the association of two opposite principles, we have seen beauty to result, of which the highest ideal must therefore be sought in the most perfect union and equilibrium possible of the reality and of the form. But this equilibrium remains always an idea that reality can never completely reach. In reality, there will always remain a preponderance of one of these elements over the other, and the highest point to which experience can reach will consist in an oscillation between two principles, when sometimes reality and at others form will have the advantage. Ideal beauty is therefore eternally one and indivisible, because there can only be one single equilibrium; on the contrary, experimental beauty will be eternally double, because in the oscillation the equilibrium may be destroyed in two ways--this side and that. I have called attention in the foregoing letters to a fact that can also be rigorously deduced from the considerations that have engaged our attention to the present point; this fact is that an exciting and also a moderating action may be expected from the beautiful. The TEMPERING action is directed to keep within proper limits the sensuous and the formal impulsions; the EXCITING, to maintain both of them in their full force. But these two modes of action of beauty ought to be completely identified in the idea. The beautiful ought to temper while uniformly exciting the two natures, and it ought also to excite while uniformly moderating them. This result flows at once from the idea of a correlation, in virtue of which the two terms mutually imply each other, and are the reciprocal condition one of the other, a correlation of which the purest product is beauty. But experience does not offer an example of so perfect a correlation. In the field of experience it will always happen more or less that excess on the one side will give rise to deficiency on the other, and deficiency will give birth to excess. It results from this that what in the beau-ideal is only distinct in the idea, is different in reality in empirical beauty, The beau-ideal, though simple and indivisible, discloses, when viewed in two different aspects, on the one hand a property of gentleness and grace, and on the other an energetic property; in experience there is a gentle and graceful beauty, and there is an energetic beauty. It is so, and it will be always so, so long as the absolute is enclosed in the limits of time, and the ideas of reason have to be realised in humanity. For example, the intellectual man has the idea of virtue, of truth, and of happiness; but the active man will only practise VIRTUES, will only grasp TRUTHS, and enjoy HAPPY DAYS. The business of physical and moral education is to bring back this multiplicity to unity, to put morality in the place of manners, science in the place of knowledge; the business of aesthetic education is to make out of beauties the beautiful.