Hey crew,

I have a question that I would love if to be answered.

Nimzowitsch states 4 reasons why exchanges take place. One of the 4 I do not understand because it is vague. It goes as follows:

"If you are strong in one file: a simple advance is enough to provoke exchanges, because your opponent cannot permit an invasion. At the very least he must try to lessen the effect of such an invasion by exchanges."

What does he mean by advance? Or by permiting an invasion?

Thanks you!

Advance refers to the advancement of a pawn.

The invasion refers to pieces entering your opponent half of the board, usually deep within their territory, and I'm guessing in order to support the advanced pawn.

Your oppponent probably want to get rid of the advanced pawn, or at least prevent the invasion, so exchanging pieces will help to relieve the tension.

Your opponent may have to concede to these exchanges even in an unfavourable position or time. eg. give up an important piece.

Hope that helped