 A nature, however, or essence …can be considered in two ways. First, we can consider it according to its proper notion, and this is its absolute consideration; and in this way nothing is true of it except what pertains to it as such; whence if anything else is attributed to it, that will yield a false attribution. …In the other way [an essence] is considered as it exists in this or that [individual]; and in this way something is predicated of it per accidens [non-essentially or coincidentally], on account of that in which it exists, as when we say that a man is white because Socrates is white, although this does not pertain to man as such.