properties of each molecule, in so far as their actual degree is concerned, are accidental; and accordingly such attributes and properties by their degree belong to the predicament of accidental _quality_. Such is the case with the attributes of every single molecule of a natural substance. As for bodies made up of a number of molecules of the same kind, it is evident that all such bodies are accidental compounds, and none of them can have any other essential attributes besides those which are common to their molecules. For the union of equal molecules is the union of _integrant_ parts, and gives rise to no new species, but only to accidental relations, quantity of mass, and quantity of volume; and consequently all the attributes and properties originating in the agglomeration of such integrant parts are simply accidental qualities. Thus _liquidity_ is an accidental quality of water, because it exhibits only the mutual behavior of distinct molecules which, of themselves, and apart from one another, are not liquid, though they have all that is needed to unite in the liquid state. And indeed, if each molecule contains the true essence of water, and yet is not actually liquid, actual liquidity has nothing to do with the essence of water, and therefore is not an essential attribute of water, but an accidental mode resulting from mutual accidental action between neighboring molecules. There are two cases, however, in which new essential attributes may be found in a body without being found in the component molecules. The first is when the component molecules undergo chemical combination; for in this case such molecules are not merely integrant but _constituent_, and by their combination a new essence is formed. Now, a new essence gives rise to new essential attributes. Thus sulphuric acid, for instance, has attributes which do not belong to its components. The second case is when the whole body is only a part of the compound essence—that is, when the specific form of that essence is a distinct substance, as in man and all animals, whose bodies are informed by a soul. In this case, the whole body and all that belongs to its organic constitution is involved in the essence of the perfect compound of which it is a part; and therefore some among the essential attributes of the compound must depend on the very constitution of the body. Thus _stature_ follows from the essential constitution of man, which includes a body having dimensions. But here, again, we must observe that, although to have some stature is an essential attribute of man, to have _this_ stature rather than that is an accidental quality; it being evident that human nature can exist without _this_ determinate stature.