E4P51D2
Demonstration — Part IV
Latin
Qui ex ductu rationis vivit, bonum quod sibi appetit alteri etiam cupit (per propositionem 37 hujus); quare ex eo quod ipse aliquem videt alteri benefacere, ipsius benefaciendi conatus juvatur hoc est (per scholium propositionis 11 partis III) lætabitur idque (ex hypothesi) concomitante idea illius qui alteri benefecit ac proinde (per 19 affectuum definitionem) ei favet. Q.E.D.
English (Elwes 1883)
(not aligned in this witness)
Modern English
One who lives under the guidance of reason desires for another the good he seeks for himself (E4P37). So when he sees someone benefiting another, his own striving to do good is aided, that is, (E3P11S), he feels joy, accompanied (by hypothesis) by the idea of the person who benefited another. Therefore (E3DA19) he approves of him. Q.E.D.