In a watch one part is the instrument for moving the other parts, but the wheel is not the effective cause of the production of the others; no doubt one part is for the sake of the others, but it does not exist by their means. In this case the producing cause of the parts and of their form is not contained in the nature (of the material), but is external to it in a being which can produce effects according to Ideas of a whole possible by means of its causality. Hence a watch wheel does not produce other wheels, still less does one watch produce other watches, utilising (organising) foreign material for that purpose; hence it does not replace of itself parts of which it has been deprived, nor does it make good what is lacking in a first formation by the addition of the missing parts, nor if it has gone out of order does it repair itself--all of which, on the contrary, we may expect from organised nature.--An organised being is then not a mere machine, for that has merely _moving_ power, but it possesses in itself _formative_ power of a self-propagating kind which it communicates to its materials though they have it not of themselves; it organises them, in fact, and this cannot be explained by the mere mechanical faculty of motion. We say of nature and its faculty in organised products far too little if we describe it as an _analogon of art_; for this suggests an artificer (a rational being) external to it. Much rather does it organise itself and its organised products in every species, no doubt after one general pattern but yet with suitable deviations, which self-preservation demands according to circumstances. We perhaps approach nearer to this inscrutable property, if we describe it as an _analogon of life_; but then we must either endow matter, as mere matter, with a property which contradicts its very being (hylozoism), or associate therewith an alien principle _standing in communion_ with it (a soul). But in the latter case we must, if such a product is to be a natural product, either presuppose organised matter as the instrument of that soul, which does not make the soul a whit more comprehensible; or regard the soul as artificer of this structure and so remove the product from (corporeal) nature. To speak strictly, then, the organisation of nature has in it nothing analogous to any causality we know.[108] Beauty in nature can be rightly described as an analogon of art, because it is ascribed to objects only in reference to reflection upon their _external_ aspect, and consequently only on account of the form of their external surface. But _internal natural perfection_, as it belongs to those things which are only possible as _natural purposes_, and are therefore called organised beings, is not analogous to any physical, _i.e._ natural, faculty known to us; nay even, regarding ourselves as, in the widest sense, belonging to nature, it is not even thinkable or explicable by means of any exactly fitting analogy to human art.