Earlier, you said that "we behave in such a way as benefiting ourselves", yet in this post you state that "all I ever said is people always act on motives in their own interest".
not quite, (I couldn't make sense of that so I had to look for the original you omited a few words from) the whole sentence is
"no one is 'evil' acting on some evil destructive intention, we all have 'positive intentions'---we behave in such a way we see as benefiting ourselves."
Meaning, we all indeed to do what we perceive as good for ourselves when we act. We may act for others good, say, saving a baby in a fire or not stealing your car, but we do that because we might fear guilt or grief of not saving the baby, or punishment of stealing the car, so we behave in a way we think is good for us, even if it is in conflict with other things that are good for us. saving a rapist from a burning building isn't really good for ourselves, and who would think of doing it? We only do something in the interests of others if it has met the prerequisite of being in our own interest.
Is our own interest always to benefit ourselves? Can it not sometimes be to harm ourselves?
In my opinion, the underground man chooses to harm himself out of spite for the fact that he is supposed to act "in such a way as benefiting [him]self"; he chooses freedom over good or benefit.
He is acting in his own interest, but not to benefit himself, unless you want to re-define benefit (refer to my earlier post for what I think are the consequences of this).
an overall benefit? no. a benefit yes. We don't always eat healthily which would benefit us in the long term, but we do eat junk food because we see it as in our interests, as benefiting us, perhaps in the realm of moodstate through the physical pleasure of it. Sometimes we do have to sacrifice long-term goods for emotional benefits, or we can get 'drained' as people say, so even if it is harmful to one part of the system, the other part is being maintained. I wrote extensively about this psycho-cybernetics issue specifically in the realm of Self-Injurous behavior about two years ago. That something is in one way harmful does not mean it isn't perceived as more greatly beneficial in another respect (in Self-Injury, it is self-harmful behavior explicitly to the physical self, but it is perceived as emotionally beneficial). Acts wouldn't be undertaken to harm of oneself unless seen as in one's own interests, as benefiting oneself in some manner, so that people risk harm to themselves (saving burning babies), or even intentionally cause it (self-injury, alcohol abuse), or even harm others (rape), does nothing to suggest we act on negative intentions or a will of anything other than a primary self-concern. The hero doesn't desire to burn himself, the self-injurer doesn't desire to be injured, the rapist doesn't desire to traumatize the victim, acts are but means to ends of our own making. (it should be clear that harm especially is but a means, we harm ourselves or others merely out of the end desire of decreasing the undesired negative emotional state).
Indeed I would not so much as throw a punch in anger if we did not want to be relieved of our anger and assume that act would do so, for even if I think someone deserves to be punched if I have no self-involvement of which my doing the punching would make me feel better I would not do it. (and if I'm paid to punch him, I see the act as a means to money, which I see as in my benefit.) You can't escape acting toward your own ends.
That should be long enough to be well boring, but I think it should make clear how benefit is regarded in a the human cybernetic system.
