And it was at that moment that I understood what was going on. Because they didn’t care. They didn’t care that they had seen it work in practice, because they already knew it couldn’t work in theory.
He is talking (at that point) about technical support for programming languages, but it feels as though his point has a much wider application – there is a point at which persuading somebody of the merits of an argument slides into persuading them to look at the problem in a different way. If we don’t do the second, the range of options for the first may end up being too constrained to be useful.