The intervention of "physical beauty" serves to explain another meaning of the words "_content_" and "_form,_" as used by æstheticians. Some call "content" the internal fact or expression (for us, on the other hand, form), and "form" the marble, the colours, the rhythm, the sounds (for us the antithesis of form); thus looking upon the physical fact as the form, which may or may not be joined to the content. It also serves to explain another aspect of what is called æsthetic "ugliness." Somebody who has nothing definite to express may try to conceal his internal emptiness in a flood of words, in sounding verse, in deafening polyphony, in painting that dazzles the eye, or by heaping together great architectural masses which arrest and astonish us without conveying anything whatever. Ugliness, then, is the capricious, the charlatanesque; and, in reality, if practical caprice did not intervene in the theoretic function, there might be absence of beauty, but never the real presence of something deserving the adjective "ugly." [Sidenote: _Natural and artificial beauty._] Physical beauty is usually divided into _natural_ and _artificial_ beauty. Thus we reach one of the facts which have given the greatest trouble to thinkers: _natural beauty._ These words often designate facts of merely practical pleasure. Any one who calls a landscape beautiful where the eye rests upon verdure, where the body moves briskly and the warm sun envelops and caresses the limbs, does not speak of anything æsthetic. But it is nevertheless indubitable that on other occasions the adjective "beautiful," applied to objects and scenes existing in nature, has a completely æsthetic signification. It has been observed that in order to enjoy natural objects æsthetically, we must abstract from their external and historical reality, and separate their simple semblance or appearance from existence; that if we contemplate a landscape with our head between our legs, so as to cancel our wonted relations with it, the landscape appears to us to be an ideal spectacle; that nature is beautiful only for him who contemplates her _with the eye of the artist_; that zoologists and botanists do not recognize _beautiful_ animals and flowers; that natural beauty is _discovered_ (and examples of discovery are the points of view, pointed out by men of taste and imagination, to which more or less æsthetic travellers and excursionists afterwards have recourse in pilgrimage, whence a kind of collective _suggestion)_; that, without the _aid of the imagination,_ no part of nature is beautiful, and that with such aid the same natural object or fact is, according to the disposition of the soul, now expressive, now insignificant, now expressive of one definite thing, now of another, sad or glad, sublime or ridiculous, sweet or laughable; finally, that a _natural beauty_ which an artist would not _to some extent correct, does not exist._