just the concept of evenness and oddness

I have the text in one mathematical book:

It certainly is a huge step beyond just the concept of evenness and oddness, which is all that the Pythagorean proof uses.

Can you explain to me what is "just" - adjective or adverb? And what does "just" mean here? I've looked some dictionary but can't choose proper meaning.


In this sentence, 'just' means the same as 'simply' or 'merely', and is an adverb. The text is saying that the Pythagorean theorem only uses concepts of evenness and oddness, but 'it' (whatever 'it' refers to) is more advanced than that.

Oxford English Dictionary: 'just' (adverb):

  1. Used to place the focus on a particular word or phrase. a. No less than; absolutely; actually, positively, really. In weakened sense: neither more nor less than, no other than; simply, merely.