E4Cap20
Chapter — Part IV
Latin
Ad matrimonium quod attinet, certum est ipsum cum ratione convenire si cupiditas miscendi corpora non ex sola forma sed etiam ex amore liberos procreandi et sapienter educandi, ingeneretur et præterea si utriusque, viri scilicet et fœminæ amor non solam formam sed animi præcipue libertatem pro causa habeat.
English (Elwes 1883)
As concerning marriage, it is certain that this is in harmony with reason, if the desire for physical union be not engendered solely by bodily beauty, but also by the desire to beget children and to train them up wisely; and moreover, if the love of both, to wit, of the man and of the woman, is not caused by bodily beauty only, but also by freedom of soul.
Modern English
As for marriage: it is certainly in agreement with reason if the desire for bodily union is engendered not by appearance alone but also by the love of begetting children and raising them wisely, and if, further, the love of both parties — man and woman alike — has as its cause not merely appearance but above all freedom of mind.