Lucy's psychological devastation in the grotesque mechanics of the commerce of slavery is comparable only to a shot straight through the heart. The devastation she feels from this gunshot wound is crippling, she can't function, but this is "lawful trade" that does not care about her emotions. A tragedy that the reader must grapple with about the reality of how the machinery of slavery destroys lives and traumatizes its victims.

Stowe is giving the reader an emotional tug on the desperation of material separation. Here, she's framing the desperation as something so visceral that you cannot as a reader of good consitution separate yourself from the feeling. Maternal love is a common draw from Stowe, and this moment serves to exemplify its emotional impact on the audience. She's tugging on the heart strings.

Mrs. Shelby's acknowledgement in "fool that I was" shows an emergence of clarity in the fog of self-deception that she has been under about the institution of slavery. The awakening of her morality is what Stowe is hoping her audience sees, and how Mrs. Shelby's faith had given her a device of morality to support slavery all these years, and now she's seeing its evil.

Brown's exchange here is highlighting how the slaveholders constructed a false narrative to justify their cruelty. The need here for moral validation from Brown shows a faltering to the moral high ground. He needs Brown to validate that that he had been kind, that their relationships transcends mere ownership. But Brown, aptly, points out that if he was, he "would not sell [him]". An irrefutable fact that he is treated as a transactional piece of property, not as a human being.

The cruelty of slavery to the helpless who could only onlook at the horrors of their oppressors is rivaled only by the direct victims. Brown's own torture where he "foresaw but too well what the result must be", where he knew what Walker was going to do to Cynthia and there was nothing he could do about it. Later, he summarizes the coercion as "Walker performed his part of the contract", and this, disgustingly, is how the oppressors made sexual violence transactional.

Wells is detailing the moral ambiguity he felt as a slave. He tricked this unsuspecting stranger into taking the lashings that were intended for him, and caused this other person harm as a result. And yet, if he hadn't done that, he would have had to endure the punishment himself. Later he says, "slavery makes its victims lying and mean", reflecting his own remorse for tricking the unsuspecting man. He says he "deeply regretted the deception", though the victimization of slavery causes this internal self-preservation. Was the deception morally wrong? Or was it simply his way of surviving? I'd argue his survival instincts took precedence over the morality of the trickery, and that's not something we can judge in retrospect.