Here’s a typical passage from the ancient Greek philosopher Parmenides.

“The thing that can be thought and that for the sake of which the thought exists is the same; for you cannot find thought without something that is, as to which it is uttered.  And there is not, and never shall be, anything besides what is . . .”

If anyone can enlighten me as to the precise meaning of the above, I would be eternally grateful – and extremely impressed.