So what is a young person to do when faced with the following situation. He is told that a Jew must believe X but he knows that X looks awfully dubious. One solution, offered up by HaRav HaGaon (HRHG) Uren Reich shlit"a (henceforth: HRHG), an up-and-coming star of the yeshiva velt who sounds like my kind of guy, deserves to be quoted verbatim:
If the gemara tells us a metziyus, it's emes veyatziv. There's nothing to think about. Anything we see with our eyes is less of a reality than something we see in the gemara. That's the emunah that a yid has to have.
This solution must seem awfully compelling to someone as obviously over-invested in the system as HRHG. Possibly less so to a young person seeking his path with nothing to guide him but whatever is left of his common sense after enduring years of mechankhim like HRHG.
So let's consider some of our protagonist's other options. He could try to persuade himself that the evidence against X is unpersuasive: science and/or history is a speculative business, scientists/historians are divided on the issue, new evidence is emerging, etc. This might work for a while. What happens when this fails? (Health Warning: If this doesn't ever fail for you, you may have unwittingly wandered into HRHG territory.)
This leaves two options: 1. leave yiddishkeit or 2. stay frum without believing X
Apparently HRHG is less frum than I am because he clearly would reject option 2 while I accept it wholeheartedly.
Option 2 comes in at least two flavors. One could argue based on the full range of traditional sources that belief in X is not necessary (or even desirable) or one could not bother with that argument. The question that arises is: what is the absolute minimal core of belief necessary to sustain any meaningful adherence to Yiddishkeit?
I believe the answer is this: one must believe -- feel in one's bones through commitment and participation -- that the Torah and the community of its practitioners are collectively endowed with a unique spark which has miraculously sustained them from some founding revelatory event in the past and will continue to sustain them indefinitely through some redemptive phase in the future.
This covers in some abstract way pretty much all the main principles that have been articulated at one time or another as ikarei emunah. But it does so in a way that really doesn't tax one's credulity too much. Certainly this kind of faith is not likely to be threatened by most scientific or historical hypotheses. It is, unfortunately, sometimes put to the test by the fact that some of those with the most influence over the path of our mesorah are total jackas [Note from Ben: the above was written by a dibbuk. I have just regained control of my typing fingers. Disregard the above.]