maybe he was talking about thinking of the moon as a flat plain facing towards the earth? if u think of two parallel lines (one for a flat earth and one for a flat moon) and then form a triangle using the diameter of the moon as one side, and its opposing angle situated at a single point on the Earth's surface then a scalene triangle may be formed...
actually on second thoughts no...this wouldn't help his argument either...forget about it :lol: haha
however, by doing this, distances between the earth and moon could be predicted, and by making the measurements at different places on the earth it may be possible to show that if the moon was flat and was parallel to the earth then the distances would be impossible. thereby proving a round moon with its diameter always facing perpendicular to the observer (round moon), rather than parallel to the earth (flat moon).
mm, sorry bout not making that very clear, if i find time ill draw a few diagrams later on