3p45d.md (450B)
1 The beloved object feels reciprocal hatred towards him 2 who hates it (III. xl.); therefore the lover, in conceiving that 3 anyone hates the beloved object, conceives the beloved thing as 4 affected by hatred, in other words (III. xiii.), by pain; 5 consequently he is himself affected by pain accompanied by the 6 idea of the hater of the beloved thing as cause; that is, he 7 will hate him who hates anything which he himself loves (III. 8 xiii. note). Q.E.D. 9 10