This piece is widely known, but I never tire of reading it. It comes from a 1906 letter by Alfred Marshall to his student Arthur Bowley (of the Edgworth-Bowley Box)
- Use mathematics as shorthand language, rather than as an engine of inquiry.
- Keep to them till you have done.
- Translate into English.
- Then illustrate by examples that are important in real life.
- Burn the mathematics.
- If you can’t succeed in 4, burn 3. This I do often.