2 comments

[ 3.6 ms ] story [ 17.0 ms ] thread
> When Knuth's 1984 The TeXbook needed an example of blackboard bold for the index, he produced ℝ using the letters I and R with a negative space between; in 1988 Robert Messer extended this to a full set of "poor person's blackboard bold" macros, overtyping each capital letter with carefully placed I characters or vertical lines.

> Not all mathematical authors were satisfied with such workarounds.

Don't mention blackboard bold in typeset material around mathematicians, it always ends in a fight.