Aristotle made it clear that there are undemonstrable first principles, a feature common to both philosophy and religion.
I observed as Moslems Arabs speak, in general, they would say: if god willing, god will help me, god wants that, god knows, god so and so. Every other word in their vocabulary is god or Allah. By being so obsessed with this god/Allah thing, are they being better human beings? No, and hell no! This god thing is nothing but superficial language, in their treacherous hearts there is nothing but hate and vengeance.
The Christ I know is a meek, forgiving humble Christ. He has nothing to do with the superficial fanatical born again evangelists of today. Their entire cry about god/prayers in school is nothing but hypocrisy. If they teach their children to pray, that should be enough. If some parents do not want their children to pray, they cannot be compelled to pray. Moslems claim that Mohammed said THERE IS NO COMPULSION IN RELIGION! The Moslem religion fanatics practice otherwise. The religion police beat women if they dont cover their heads, or if someone is found eating in Ramadan! Our fanatic born again Christians gang would beat our children if they did not pray before meals!
If you mean axioms, "existence exists," "we are conscious and existence is what we are conscious of," and "a thing is what it is, or A is A," they are demonstrable. Since they are axioms, not derived concepts, because there are no more basic concepts from which these could be logically deduced, they cannot be logically proved, in the usual sense, because logical proof pertains only to derived concepts. The axioms, however, cannot be denied without producing a logical contradiction, because all logical proof depends on them, and they are implicitly assumed in all other knowledge or logical statements.
As for demonstrating them. if you are reading this, then you exist and what you are reading exists and you are consious both of yourself and what you are reading, and what you are reading is what you are reading and you are you. To deny any of these you must assume them in the denial, contra-hypothesis.
Now I copied WOSG to this response because he suggested the same commonly held mistake in Post #42:
My point is: All systems of belief require faith of some sort - even Science!
But sceince does not require any faith of the (just believe without reason) kind at all. The axioms are not assumptions, they are discovered rationally, and verified logically, by the very fact they cannot be denied without contradiction. They are the foundation of all other knowledge, including science.
Hank