Summa summae S. Thomae, Tomus II

I say 1°: The quantity or essential inequality of sins is derived from the object in point of gravity¹.

It is proved. Thence is sought the essential quantity or gravity of sin, whence its species is sought². But the species of sin is derived from the object, as we said in the places soon to be cited. Therefore.

I say 2°: The essential inequality of sins is also sought per se and caeteris paribus from the virtues to which they are opposed³; so that that sin is the more grave which is directly and principally opposed to the nobler virtue.

This conclusion follows from the preceding; because, the nobler the virtue against which a sin is opposed, the more excellent is the object about which it is concerned. But it was said in the preceding conclusion that the essential gravity of sins is derived from the object. Therefore.

Understand both these conclusions 1º per se, because per accidens a sin whose object is more grave and is opposed to a nobler virtue can, by reason of the imperfection of the act or the lightness of the matter, be venial; and another whose object is less grave and is opposed to a lesser virtue, mortal. 2º Understand it caeteris paribus, so that the vices between which the comparison is made are concerned with the primary object of the virtue to which they are opposed; so that, if a supreme vice is opposed on one side to the supreme virtue, so also on the other: for want of which, hatred of one's neighbor, for example, although opposed to charity, the most noble of virtues, is nevertheless not the most grave of sins, because it is not opposed to the primary object of charity, which is God.

I say 3°: The gravity of sin is also sought from the circumstances⁴; because each thing is apt to be increased by that from which