Just in case what I wrote earlier was not entirely clear or perhaps
elliptical, I would like to add the following. First, I have pared down and
recast your argument for clarity - I hope I have not misrepresented what you
are saying (psl feel free to rephrase if you wish):
Proposition: Suan Lu Zaw has arrived at the knowledge that Pali was
the
language of the Buddha because:
Premise 01: Ancient Buddhist masters said that (Pali was the
language of the Buddha).
Premise 02: Ancient Buddhist masters do not lie.
Conclusion: Therefore Pali was indeed the language of the Buddha.
There are various problems with this argument - the logical faults and the
possible factual faults.
First, the logical faults (do.sa). Your argument seems to display at least
the following fallacies which, to use Westerm terminology, are: an ignoratio
elenchi (irrelevent conclusion) or a possible non sequitur, an argumentum ad
verecundiam (appeal to authority), a dicto simpliciter (generalization) and
an implied argumentum ad antiquitatem (appeal to antiquity). If you are not
sure what precisely each of these are, could you possibly look them up
yourself.
Secondly, the possible factual faults relate to the individual premises -
even if your argument were logically true, both your propostion and your
conclusion may still be factually false (or they could even be factually
true but the argument logically false). In other words, logic in itself
doesn't solve the problem of verifying your basic assertions (premises)
which support arguments. To do that, you need some other tool - primarily
scientific or empirical enquiry which you have not adduced.
I hope this helps.
Best wishes,
Stephen Hodge
PS: I have a feeling that that you might be tempted to resort to a tu quoque
argument to answer the above - don't bother because that is also a logical
fallacy :)