What does "end with an empty board" mean?

Question

I got this statement from Fundamental Chess Openings by Paul van der Sterren, and I don't understand what it means to end up with an empty board:

However, since the human brain and even the computer is still not capable of completely seeing through (and thereby destroying) chess as a whole, in practice opening theory does not end with an empty board but in positions where there is a certain consensus about how they should be assessed, for instance 'chances are equal' or 'White (or Black) has the advantage'.

Answer 1

in practice opening theory does not end with an empty board but in positions where there is a certain consensus about how they should be assessed,

If chess had been solved then the logical conclusion of opening theory would be the end of the game, i.e. "an empty board" where only kings are left or only kings plus material insufficient to deliver mate. Note that there is an implied assumption here that chess is a draw since a checkmate position would very much not be "an empty board".

Since we don't have that complete knowledge the opening phase is generally regarded as having ended when development is complete.

Answer 2

(I can't make out which book you are referring to: I find two or three books with that or a very similar title. So I can't decide myself.)

The author/authors seem likely to be trying to give an impression of a'chess position spectrum', from one end ('full board') to the other ('empty board'). As metaphors go, it is probably not an attempt to express a definite, detailed and unassailable truth, but rather an impression of a continuum.

In art terms, it would be 'impressionistic' language, not 'realistic' language. Don't over-interpret. Don't get stuck. Read on. When you have read as much of the book as you can stand, go back and look again at that and other passage that you may have marked with a '?' in the margin. (And don't get stuck on that word 'margin' either -- you mark it any way you like, of course.)