That wasn't Sussman's point. The problem is that the same notational forms -- the same orthographies, if you will -- can mean different things in different cont

That wasn't Sussman's point. The problem is that the same notational forms -- the same orthographies, if you will -- can mean different things in different contexts. It doesn't help at all that one must, on occasion, slip from context to context in the same argument, producing adjacent or near-adjacent statements that have similar general forms but wildly different meanings. His solution to the problem was to use a notation that also happens to be valid statements in a computer language he had a large hand in designing. That part isn't necessary, but disambiguating mathematical notation by some means is.