PLEASE ANSWER! What were the means by which a person could come to know the essential forms of reality?

Based on "Allegory of the Cave"

"if i have seen farther than others," said newton, "it is because i have stood on the shoulders of giants." who were the giants to whom newton was referring? could this be said of any scientific accomplishment? explain.

What is the term for a short statement about history that has not been yet been proved

What is a characteristic of the paleolithic period