Considered with regard to their duration, the objects composing the organic and the inorganic world differ essentially. In the former this period is determinate and definite, and, although it varies greatly, it depends in a great measure on circumstances inherent in the in dividuals ; in the latter it is indeterminate and indefinite, and when the objects composing it cease to be, it is generally in consequence of circumstances exterior to themselves. Organized beings exist for a limited time and in oppo sition to many of the physico-chemical laws ; unorganized beings exist indefinitely, and only in harmony with the whole of 'these laws. Organic beings continue to exist in conse quence of a kind of reciprocal action with external things, and especially by virtue of an incessant change and renewal in their con stituent elements. The very condition of ex istence of an unorganized body is quiescence ; any new action between its molecules them selves, or between these and others external to them, any addition to, or subtraction from, its component parts, implies the destruction of its individuality.
In the organic world, new forms result from the actions of forms already existing, which have the wonderful property of producing others similar to themselves; and this in virtue of no general physico-chemical law, but of an especial power inhering in each organized being individually. There is nothing like this faculty of procreation or of generation in the in organic world. When a crystal is produced, it is necessarily at the expense of one or of others that have already existed, or of a combination of the elements of these ; destruction is here a necessary preliminary to production, and the process is simply one of re-formation, not of genesis or creation. Neither in the re-forma tions of the inorganic world do we find that the forms are always necessarily the same as those which preceded them : the crystalline form does not depend on the nature of the integral molecules, but on their mode of aggregation and number. In the organized world, again, nothing is more certain and fixed than that the form of the new being shall resemble that which gave it birth.
The last distinction we shall mention under this head of material composition and physical qualities between organic and inorganic bodies is, perhaps, less striking, though not less in teresting on that account : it is this,—that whilst in inorganic bodies the composition is quite de terminate, in organised beings, although con stituting particular species, the composition may present individual differences or modifica tions. These are designated by the titles tem perament, constitution, 4-c. There is no corres ponding modification recognizable in the in organic world.
From what has now been said, it appears that organized and unorganized bodies differ essentially from one another in their general physical qualities and material constitution. The form of the organized being is determinate, and its outline is rounded or undulating ; its size ; its duration is temporary ; its composition is an assemblage of heterogeneous parts, of solids and fluids, arranged so as to compose a variety of fibrous and cellular tissues, and aggregates of organs or parts differing from one another in their form, struc ture, and functions, but all nevertheless mu tually dependent one upon.the other, and con
curring to a common end,—the preservation of the individual, which has place by virtue of an internal activity denominated amidst incessant changes and renovations of the matter entering into its composition, and the continuation of the species, which is a genesis or creation, implying neither destruc tion nor alteration in the mode of being of the individual or individuals from whom the new formation springs.
Actions of unorganized and of organized objects. — But form, size, material composi tion, duration, mode of origin, &c. are not the only particulars in the history of or ganic and inorganic bodies which are capa ble of being contrasted, and in which differences may be made to appear.
All that exists is active; every entity performs actions, or manifests forces by which its own ex istence is continued, and by which it participates in the various phenomena of the universe. Of these actions or forces there are two grand classes, the one general, the other special : the the physico-chemical laws which per vade space and include the universe ; the second are the vital laws, which embrace within their dominion plants and animals, or things organized and having life.
The most general of all the forces possessed are those of attraction and repulsion, which inhere in, and are manifested by, all existing things, organic as well as inorganic. Every object gravitates or has weight, coheres in its several parts, exhibits chemical affinities, and yields to the expansive influence of caloric. Inorganic objects exhibit these general forces alone, and are absolutely under their control. Organized bodies are also subjected to the same general forces ; but they are often modified, nay, they are sometimes even abrogated and set at nought by vegetables and animals alike, in virtue of the special powers inherent in themselves. These special powers have, in fact, the singular property of subtracting, in various degrees, the beings they actuate from the in fluence of the general laws of creation. In stead of obeying the universal law of gravita tion, vegetables, for instance, shoot upwards, and propel their juices from the roots to the leaves animals also distribute their blood in opposition to the laws of gravitation, and by their powers of motion overcome the universal physical law that tends to fix them in one place. The force of cohesion is not a merely passive property in the organized as it is in the unorgan ized world, and the laws of chemical affinity are especially set at nought both by plants and anima!!, their constituent elements being even generally united into combinations the con trary of those which these laws ordain. Animals and vegetables are farther abstracted from the general law of caloric, the more perfect of them at least having a specific temperature, inde pendent of that of the medium which sur rounds them, and which varies in conformity with changes in the peculiar actions of which in them it is the product.