I agree. For even the most basic understanding of the world, a feel for mathematics is absolutely necessary.
While I wouldn't quite go as far as Heinlein does, his opinion on the matter seems to be:
Anyone who cannot cope with mathematics is not fully human. At best he is a tolerable subhuman who has learned to wear shoes, bathe and not make messes in the house.
If nothing else, people should learn statistics. Statistical thinking is absolutely essential to understand most social, economic, and political issues in the world, and people who just don't get it are mentally crippled. I see this all the time.
While I wouldn't quite go as far as Heinlein does, his opinion on the matter seems to be:
Anyone who cannot cope with mathematics is not fully human. At best he is a tolerable subhuman who has learned to wear shoes, bathe and not make messes in the house.