ישעיהו מ:כא פירוש: רש״י ואבן עזרא

Do you not know...the foundations of the earth Who founded it, and you should have worshipped Him.

הלא תדעו Have ye not known by your own common sense, which is the most important source of knowledge ;

הלא תשמעו have you not heard; have you not been informed by others;