| Quote #7
Such is the vulpine slyness of Dame Nature, that, till now, Tess had been hoodwinked by her love for Clare into forgetting it might result in vitalizations that would inflict upon others what she had bewailed as a misfortune to herself. (36.86)
Tess realizes that if she manages to persuade Clare to stay with her by getting him to consummate their marriage (i.e., to have sex with her), she might get pregnant. But to call those potential children "vitalizations" sounds awfully clinical and distant. She thinks of their possible children as future sufferers at the hands of an unjust world, and simply as "vitalizations" – living things. And living things, as we know from reading Hardy, suffer.
| Quote #8
She was ashamed of herself for her gloom of the night, based on nothing more tangible than a sense of condemnation under an arbitrary law of society which had no foundation in Nature. (41.33)
Tess sees the dying birds in the early morning, and puts them out of their misery out of pity. She realizes that she's not actually the most miserable living creature in the world – she hasn't been shot by hunters and left for dead. She's only been "condemn[ed]" by "an arbitrary law of society." So again, there's a distinction being made between Nature's laws, and the laws of society. The only law Tess "broke" (sex before marriage) is a social law, and one that has "no foundation in Nature."
| Quote #9
"I'll always be ugly now, because Angel is not here, and I have nobody to take care of me. My husband that is gone away, and never will love me any more; but I love him just the same, and hate all other men, and like to make 'em think scornful o' me!" (42.5)
Angel might have left her, but Tess remains fiercely loyal to him to the point of making herself ugly so that other men won't admire her good looks. Her idea of marriage seems to be that no other men should even look at her if she can help it. But really, her decision to make herself ugly is a practical one – she was getting harassed on the road.