<P> The unknowns of pyramid construction chiefly center on the question of how the blocks were moved up the superstructure . There is no known accurate historical or archaeological evidence that definitively resolves the question . Therefore, most discussion on construction methods involves functional possibilities that are supported by limited historical and archaeological evidence . </P> <P> Historical accounts for the construction of the Egyptian pyramids do little to point definitively to methods to lift the blocks; yet most Egyptologists refer to these accounts when discussing this portion of pyramid construction . Thales, according to the philosopher Hieronymus (3rd century BC) visited the Egyptian pyramids during the 7th century BC and by using the intercept theorem, also known as Thales's theorem, measured their height and thus their volume . The first historical accounts of the construction of these monuments came centuries after the era of pyramid construction, by Herodotus in the 5th century BC and Diodorus Siculus in the 1st century BC . Herodotus's account states: </P> <P> This pyramid was made like stairs, which some call steps and others, tiers . When this, its first form, was completed, the workmen used short wooden logs as levers to raise the rest of the stones; they heaved up the blocks from the ground onto the first tier of steps; when the stone had been raised, it was set on another lever that stood on the first tier, and the lever again used to lift it from this tier to the next . It may be that there was a new lever on each tier of steps, or perhaps there was only one lever, quite portable, which they carried up to each tier in turn; I leave this uncertain, as both possibilities were mentioned . But this is certain, that the upper part of the pyramid was finished off first, then the next below it, and last of all the base and the lowest part . </P> <P> Diodorus Siculus's account states: </P>

What is the foundation of the great pyramids