The subjective parts of a virtue are its species: and the species of a virtue have to be differentiated according to the difference of matter or object. Now temperance is about pleasures of touch, which are of two kinds.
 Thomas Aquinas, Summa Theologica (1274). copy citation

add
Author Thomas Aquinas
Source Summa Theologica
Topic virtue pleasure
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“The integral parts of a virtue are the conditions the concurrence of which are necessary for virtue: and in this respect there are two integral parts of temperance, shamefacedness, whereby one recoils from the disgrace that is contrary to temperance, and honesty, whereby one loves the beauty of temperance. For, as stated above (Q. 141, A. 2, ad 3) , temperance more than any other virtue lays claim to a certain comeliness, and the vices of intemperance excel others in disgrace.
The subjective parts of a virtue are its species: and the species of a virtue have to be differentiated according to the difference of matter or object. Now temperance is about pleasures of touch, which are of two kinds. For some are directed to nourishment: and in these as regards meat, there is abstinence, and as regards drink properly there is sobriety. Other pleasures are directed to the power of procreation, and in these as regards the principal pleasure of the act itself of procreation, there is chastity, and as to the pleasures incidental to the act, resulting, for instance, from kissing, touching, or fondling, we have purity.
source