The general law, then, respecting just or economical exchange, is simply this:--There must be advantage on both sides (or if only advantage on one, at least no disadvantage on the other) to the persons exchanging; and just payment for his time, intelligence, and labour, to any intermediate person effecting the transaction (commonly called a merchant): and whatever advantage there is on either side, and whatever pay is given to the intermediate person, should be thoroughly known to all concerned. All attempt at concealment implies some practice of the opposite, or undivine science, founded on nescience. Whence another saying of the Jew merchant's--"As a nail between the stone joints, so doth sin stick fast between buying and selling." Which peculiar riveting of stone and timber, in men's dealing with each other, is again set forth in the house which was to be destroyed--timber and stones together--when Zechariah's roll (more probably "curved sword") flew over it: "the curse that goeth forth over all the earth upon every one that stealeth and holdeth himself guiltless," instantly followed by the vision of the Great Measure;--the measure "of the injustice of them in all the earth" ([Greek: aute he adikia auton en pase te ge]), with the weight of lead for its lid, and the woman, the spirit of wickedness, within it;--that is to say, Wickedness hidden by Dulness, and formalized, outwardly, into ponderously established cruelty. "It shall be set upon its own base in the land on Babel."[53] [53] Zech. v. 11. See note on the passage, at pp. 191-2.