I've asked the first question. The response, which seems to make a certain amount of sense, still begs further questions, which I think need to be articulated.
Is religion nothing more than a psychological yearning? Then, received religious norms which we give names like "Christianity", "Islam", "Buddhism", and so on are nothing more than a socialized structure given to these inchoate, personal yearnings. These latter phenomena are the groups answer to the individual question, it would seem.
If that is a fair description of the dynamics according to the understanding given, it would at the very least explain the often violent reaction many people have when their beliefs are questioned. Rather than an attack on some external, received ideas, they are understood to be a deeply personal attack on an individual's sense of herself in relation to the Universe. Questioning the very existence of God becomes a surrogate for questioning an individual's grasp of reality.
Yet, we are still confronted with certain questions that cannot be addressed by turning this issue in to an interplay of interpersonal psychodynamics. What of those individuals who insist that their belief comes not through a process of pyscho-social integration, but rather as a result of intervention from "outside" (to use an ill-defined term)? Do we insist that individual's experience is not in fact from outside their understanding, but rather from deep within their psyches? What of various religious groups attempts to regulate these experiences through what could be called (to use a very Christian term) the monastic tradition? Even loosely organized, local deities have their shamans, their holy men and women, whose understanding and experience outstrips that of others, and are given pride of place in their communities for this very reason. Are they nothing more than borderline personalities whose disorders are misconstrued by a community unfamiliar with the workings of the human mind? This question, to me, creates a host of issues, not the least of them being: Do we really understand the human mind well-enough, thoroughly enough, not only to make the assertion that religious belief is such a thing, but that others who do not do so are insufficient in their grasp of it?
Seems pretty haughty to me to tell other social groups they don't understand their own world as well as we do, who observe it from outside.
There is a functional understanding and approach to religious belief, typified by the work of, say, Henry Nelson Weiman, that would seek to understand religious belief solely through its social and psychological function, without reference to any ideological or theological content. Yet, without even an elementary grasp of that content, how can any interpretation of religious practice be anything other than guesswork? Fortunately, Wieman indeed had that grasp - even though he rejected it - and his work is an important part of any understanding of American religious belief and practice.
To stand outside any set of religious beliefs and insist that those inside are merely responding to a deeply-felt human need, given shape and substance by various historic religious practices really doesn't answer the question as to why religion has continued to play an important part in human affairs, even in the West, which pronounced over the alleged corpse of religious belief centuries ago.
I have no answer to these and more questions; particularly since, as Charles Taylor details, the process of secularization in the West has a kind of inexorable quality to it. I only ask them because I have a sense that the whole "its just a human need for transcendence" response just doesn't satisfy a basic principle of scientific inquiry - not only does it not address all the relevant phenomena, it doesn't offer opportunities for further understanding.