To discuss or deal with a topic (to talk about something, analyze or treat it).
専門家はその問題を論じるために会議を開いた。
Experts held a meeting to discuss the issue.
その本は現代社会の問題を広く論じている。
The book broadly deals with problems of modern society.
論じるべき点がまだいくつか残っている。
There are still some points left to be discussed.
To argue or dispute (to present arguments for or against something).
彼らは理論の正当性について熱心に論じ合った。
They argued passionately about the validity of the theory.
その結論には疑問が多く、複数の研究者が反対の立場から論じた。
There were many doubts about that conclusion, and several researchers argued against it.
Used often in negative sentences to indicate whether something is worth taking into consideration or making an issue of (e.g., 'not worth discussing').
そんな小さな問題は論じるまでもない。
Such a small matter is not worth discussing.
証拠がない以上、その点を論じる意味はない。
Without evidence, there's no point in arguing that point.