Hi,
Definitely Durkheim. Try his term "
anomie". His major work,
Le Suicide, he puts forth that the suicide rate is influenced by two variables:
a) integration of the individual into society
and
b) regulation of the individual by society.
Extremes tend to favour suicide:
Integration:
- Too much: Altruistic suicide (kamikaze bombers, killing yourself so that your family can profit from your life insurance...)
- Too little: Egoistic suicide (your life is "empty", if your goals don't match with the goals of those around you; you can't do what you want)
Regulation:
- Too little: Anomic suicide (every decision becomes a chore; you don't know how to go on)
- Too much: Fatalistic suicide (here's the kicker: he only mentions that type because of logical necessity, and then only in a footnote. He claims examples are hard to find. - Later sociologists have then gone and looked into that type [slums etc.])
He's also done work on education (stressing "positive authority" - a kind of authority that comes from "leading by example"), and religion (people really worship the community). Durkheim was a major influence on both structuralism and - perhaps more important for you - systemic functionalism (you might check out Talcott Parsons and Robert K Merton, though they're not very much concerned with individual action).
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Erving Goffman is more outlining how people deal with social expectations. His philosophy is hard to make out and experts disagree. His focus is on coping mechanisms.
Presentation of self is a good one, talking about the roleplaying aspects of society. He points out a phenomenon, that's probably of interest to you:
There are core role expectations, e.g. all the things a doctor is supposed to do. But there are also expectations on how to play the role. A key element is "role distance". If you don't display this, people are likely to call you "over-adapted" (I don't remember the proper term). You don't want to be reduced to your position; but neither do your colleagues want to reduce you to your position. So there's some sort of pressure to show yourself beneath the role (you don't have to be honest, but you have to show that there's more to you than just the role).
This can easily be twisted into an argument that apparant "individualism" is really an attempt to fit in (your character's "box within the box" argument could profit from Goffman's concept of "role distance"). [Also check out "Stigma", Goffman's book on how to deal with being obviously different.]
The problem, though, is that Goffman himself was somewhat of an enfant terrible in sociology/social psychology, who did his own thing. He's a very amusing read if you like wry humour with the tendency to get dark at times. Interviewers called him hard to interview; he'd turn the questions around and they'd feel like they're part of his current project. I suspect that Goffman would neither support nor counter your character's opinion, as his real interest was with coping mechanisms.
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Marxist philosophy runs you into problems with the "being successful" part of the arguments, IMO. If you have a boss, you're being exploited. That's not really what you want to get to get across, I think.
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You might also want to take a look at Arnold Gehlen, whose idea of man as a "deficient creature" ("Mängelwesen"; I don't know how they translated this) has been influential in pedagogy. Man is deficient (no fur, laughable claws and teeth...) and compensates with society. This idea has been very influential in education, in the sense that education "completes" the person. I'm not too familiar with Gehlen myself, though. It just came to mind.