expression
it goes without saying; needless to say
Fixed expression used to emphasize that something is so obvious it is foolish to even mention it. Often followed by a clause stating the obvious fact.
言うも愚か、健康が一番大切だ。
It goes without saying that health is the most important thing.
言うも愚かなことだが、遅刻は厳禁だ。
Needless to say, being late is strictly forbidden.
Similar meaning but more common and slightly less emphatic; 言うも愚か carries a nuance of 'it would be foolish to even say it'.
A fixed phrase combining 言う (to say) + も (even) + 愚か (foolish), literally 'even saying it is foolish'.