There is even a distinction between the organized and unorganized world to this extent, —that while the physicochemical laws do minate the inorganic world rigorously, and the bodies that belong to it seem to have begun to be as they continue to exist through, or in harmony with, heir prescriptions, no organized body known has either sprung into being or continues to exist through the agency of purely physical or purely chemical forces. The whole of the special properties of organized beings consequently must be held to be effects of the agent denominated life, and of the laws which this agent originates. The organized world is, therefore, a creation within a creation, a some thing superadded to the material universe and to the generally pervading forces that keep its parts in their places, and endow them with what may be called their necessary pro perties.
Nor is it only whilst endowed with life that organized differ from unorganized beings. Many of the distinguishing and peculiar pro perties of these remain for a season at least after life has left the organization it had built up. • The extensibility and elasticity of the tissues of animals especially, were held by the distinguished Bichat as even independent of life, which he owned increased their energy, but which he denied as their cause, seeing that they continue to exist after death. These pro perties are undoubtedly peculiar, and are at all events effects of forces which life has called into play, both the tissues which possess elasticity and contractility, and these qualities themselves having been engendered under the influence of vitality.
In these properties, forces or capacities of action common to all the objects of nature, unorganized as well as organized, we see the objection to the old denomination of inert, which was applied to one of the great classes. Nothing that exists is inert or inactive ; but organized have an infinitely wider field of action than unorganized bodies. Let us, in illustration of this position, examine in succes sion the various actions by which bodies gene rally originate, continue their existence, un dergo such modifications as they present in the course of their existence, and by which they come to an 'end or die.
Origin.—Unorganized bodies, minerals for example, commence their existence from the instant that circumstances exterior to them selves detach them from the mass of some other mineral, precipitate them from a state of solution in a fluid, or bring their constituent elements into a position in which they can combine together. In this, it is evident, there is nothing like generation, as the term is applied to organized bodies, which all alike, vegetables as well as animals, spring from a molecule, an atom, which has once belonged to, and which has proceeded from, a being similar to themselves. Vegetables spring from seeds, animals from eggs. Organized beings, therefore, are engendered, their existence is a consequence of that of other beings like themselves ; and in their succession they depend one upon another. Minerals, on the
contrary, have no powers of reproduction ; they cease to be, if at any time they originate another mineral, and they are individually in a state of perfect independence.* In the mode in which organic and inorganic bodies continue their existence, there is also a striking dissimilarity. In the inorganic world we observe no actions tending to preserve the individual, other than those which have pre sided over its formation : it continues to exist through the continuing agency of the affinities and of the attraction of cohesion which called it into being. Animals and vegetables, on the contrary, have special powers for their pre servation superadded to those by the peculiar agency of which they have been created. Inorganic bodies exist through the absence of all change in their interior ; organized beings exist by force of change : there are two pro cesses, one of renewal, the other of decom position, perpetually going on within them ; they are continually appropriating from bodies exterior to themselves a quantity of matter which they have the singular faculty of ela borating into their proper substance, and they have at the same time the power of withdraw ing portions of the matter which already forms them, and rejecting these from their interior as no longer fitted for their preservation. Vege tables, by means of their roots and their leaves, draw from the earth and from the air materials which they elaborate into juices fitted for their nourishment, at the same time that they throw off, especially by means of their leaves, a por tion of the matter which had been absorbed, either as superfluous or as improper to enter into their composition. In the same manner ani mals appropriate to themselves various amounts of matter in the shape of atmospheric air and food, from which they prepare a fluid proper for their maintenance, at the same time that they, by virtue of peculiar processes, with draw from their bodies such portions of mat ter as have already fulfilled their destination, and cast them out under the form of excre tions. Organized bodies, consequently, are preserved as individuals by a process of nu trition, a process which implies dependence on other bodies, and alternate appropriation and rejection of the particles of these ; the ex istence of an organized being, in fact, only con curs with the presence and appropriation of substances external to itself, with a perpetual accession of matter on the one hand, and of its rejection on the other, whilst unorganized bodies are more certainly continued, as their state of isolation or abstraction from all ex ternal influences is more complete. Organized beings, in a word, continue to exist by virtue of certain inherent especial powers ; un organized simply by virtue of the general powers that pervade the universe in harmony with which they were originally framed.