Just for the record, I thought this passage from [Omar Khayyam's algebra book][1] (p.49) should be here. In particular, it shows how hard it was to to tie the understanding of powers to geometry > I say: what algebraists call square-square is an imaginary concept in > continuous quantities. It has no existence in any way in materialistic > objects. For continuous quantities, the terms square-square, > square-cube and cube-cube are used to denote the number (coefficient) > of the object (variable). Things share the sort of the quantity (all > variables have the same type of coefficient: a real number), as is > continuously shown by He who has the ultimate knowledge (God). The > things that algebraists use to denote objects and quantities are: > number, root, square and cube. The number has to be taken as an > abstract concept. It has no existence unless it is individuated by > things... > Square-square, which, to the algebraists, is the product of the square > by itself, has no meaning in continuous objects. This is because how > can one multiply a square, which is a surface, by itself? Since the > square is a two-dimensional object (geometrical figure), and > two-dimensional by two-dimensional is a four dimensional object. But > solids cannot have more than three dimensions. All objects in algebra > are generated from these four genera. And anyone who says that algebra > is a trick to determine unknown numbers is wrong. So don’t pay > attention to these people. It is true that algebra and equations are > geometrical things... [1]: https://archive.org/details/AnEssayByTheUniquelyWiseabelFathOmarBinAl-khayyamOnAlgebraAnd