Misc: What was King Arthur's sword called?

Questions

Trivia : Who said "In my free time I do differential and integral calculus"?

Trivia : Who said "The no-mind not-thinks no-thoughts about no-things" ?

Trivia : Who said 'Everything must either be or not be, whether in the present or in the future'?

Trivia : Who said 'Give me a firm place to stand and I will move the Earth'?

Trivia : Who said 'So far as the laws of mathematics refer to reality they are not certain. And so far as they are certain, they do not refer to reality.'?