How we cite our quotes: Citations follow this format: (Chapter.Paragraph)
Quote #4
On these lonely hills and dales her quiescent glide was of a piece with the element she moved in. Her flexuous and stealthy figure became an integral part of the scene. (13.14)
Once again, the narrator associates Tess with nature. Here, she actually seems to become one with nature. She becomes "an integral part" of the landscape, and is "of a piece" with nature. It's more of the earth goddess thing again, although it sounds pretty hippy.
Quote #5
Walking among the sleeping birds in the hedges, watching the skipping rabbits on a moonlit warren, or standing under a pheasant-laden bough, she looked upon herself as a figure of Guilt intruding into the haunts of Innocence. But all the while she was making a distinction where there was no difference. Feeling herself in antagonism she was quite in accord. She had been made to break a necessary social law, but no law known to the environment in which she fancied herself such an anomaly. (13.15)
Tess thinks that she's broken a universal law – something natural and fundamental. But really, the only law that she's broken is a social law – one that humans invented. It's a "necessary" social law, the narrator adds (he doesn't go so far as to say that the taboo against pre-marital sex is a bad one), but it's not a natural law. And notice also that he says that she was "made to break" that law – in other words, she isn't at fault, and the sin isn't hers.
Quote #6
So passed away Sorrow the Undesired – that intrusive creature, that bastard gift of shameless Nature who respects not the civil law. (14.58)
It's another juxtaposition of nature and civilization – Sorrow was a "natural" child in that he (or she?) was born according to "natural" laws, as opposed within the socially sanctioned bonds of marriage.