Yesterday in the subway I noticed something that set my thoughts racing: a young man with shoddy clothes, unkempt hair and bare feet. Bare feet, in the subway! My subconscious mind immediately sent out the usual signal: social outcast, avoid. However, a few seconds later my conscious memory kicked in, and completely changed the entire thought process: it said ‘why outcast?’. I suddenly remembered it was perfectly normal to see bare feet in India, at home and on the street. Bare feet could hardly make a social outcast there. And that realization led to the question of why my perception changed so dramatically, of what this dichotomy actually meant.
The non-universality of social norms
Social norms are a consequence of society, of the agglomeration of people under a common banner. Society is an entity that is made for and by the people that constitute it. It exists at the discretion, and for the benefit, of its people.

The Swastika on a Harappan seal: perceived as a symbol of human evolution
The people that constitute a society determine what it stands for, and where its bounds of propriety lie. As such, these bounds of propriety are liable to be different from people to people. Social norms, then, are liable to vary over time and space: what is deemed appropriate by the people of Australia today may be deemed inappropriate by the people of Angola tomorrow. Opinions and perception, then, that are based on social norms are bound to be non-universal in nature. Take the case of bare feet for instance: bare feet in Boston could get you branded as a social misfit, and yet in India the same bare feet would make a perfect social fit. Your perception of bare feet would itself be perceived dramatically differently on Indian soil in accordance with the norms prevailing there. Who, then, is a social misfit and where? The guy in Boston for walking around with bare feet, or you in India for holding an opinion that contradicts local mores?
The influence of norms on perception
Although our perceptions are supposed to arise from within us, it often happens that those perceptions are simply the manifestations of social influence. Take for instance the popular perception of the swastika. The swastika is perceived

The Swastika as the Nazi emblem: perceived as a symbol of racial segregation
in India as a symbol of evolution and progress, while in Europe, due to its Nazi connotations, it perceived as a symbol of racial segregation. Does this mean that one particular perception of the swastika is right while the other is wrong? The swastika symbol, after all, is simply just that: a symbol. It can be taken to mean whatever you want it to mean. Its perception should only be a result of individual thought, and yet it is obvious that its perception actually is a result of social thought. Indeed, would I be necessarily wrong in thinking of the swastika as something completely different: say as a symbol of the sea? Would that necessarily make me a weirdo?
The socially conditioned pathway of thought
I am fairly confident that, given a similar context, almost all my friends and acquaintances would have arrived at the same conclusion about the anonymous young man on the subway. I believe this because I believe that my thought process would not have been very different from most others’. And this itself is hardly surprising because, after all, my acquaintances all belong to the same society, and are exposed to the same social norms. As such, it is only natural that all of us have a certain common fundamental process of thought: of processing an observation into an interpretation into a conclusion. A thought pathway, so to speak.
Bare feet + unkempt hair + shoddy clothes = Social outcast -> Avoid
Designer shoes + immaculate hairdo + form-fitting clothes = High society -> Associate
Although we may find it difficult and inconvenient to accept, our thought processes are significantly influenced by the society that surrounds us. The social norms that envelope us determine not only our words and deeds, but also our perception of the words and deeds of others. For every conversation with every acquaintance, our subconscious mind automatically tends to fit our perceptions of others into pre-allocated stereotypes of humanity: good/bad, conservative/liberal, moral/immoral, etc. Instead of interpreting a phenomenon or utterance based on our own knowledge of intent and context, our subconscious mind tends to adopt the interpretation laid down in established social norms. In other words, our thoughts and perceptions are often the instinctive results of successful social conditioning.
The consequence of social conditioning

Money - it's what we've been inculcated to measure the worth of a man by. But how correct is this?
Social conditioning, says Wikipedia, is the process of inheriting tradition and cultural transmutation passed down through previous generations. It is, in essence, the process by which a society induces its inhabitants to adhere to a certain common code of thought. Since society is a creature of evolution, it is, by very definition, an entity that is continuously evolving. Norms and mores that are felt “appropriate” by a particular generation of a society are a direct result of the circumstances and contexts that that generation of people experienced. With time, these circumstances and contexts are guaranteed to change. Change in the norms and mores of society, are therefore, inevitable. Social conditioning, however, interferes in this process by dictating the scope and even applicability of change based on certain pre-determined standards. By fixing as constant the norms and mores, social conditioning essentially obstructs the process of evolution of society, thereby endangering its very survival.
Towards unfettered thinking
Social norms are essentially the crystallization of consensus-based societal opinion. They derive from the perceptions and thought processes of individuals sharing certain common fundamentals. Thus, the morals, norms and mores that the people of a society are expected to live by are a product of the collective conscience of the said people themselves. In other words, it is the people that determine what the norm is and isn’t. As a corollary to this, it can be inferred that each individual opinion and perception has a certain specific part to play in the shaping of social norms. Indeed, it can even be said that among the duties of an individual towards society is the duty to contribute to social opinion by developing, nurturing and deploying a unique individual opinion. And this can only arise as a result of an independent and unfettered application of personal perception and thought process.