Help identifying the  author of this phrase
Some time ago I read on the Net something like "you learn a thing only when you really need it" (e.g., learning a new programming language). If memory serves me well that was a sort of "law" or "principle", ironic or not, and I cannot remember its author's name.

Any help in identifying the correct phrase and its author?

Thanks in advance.

Help identifying the  author of this phrase
===

Some time ago I read on the Net something like "you learn a thing only when you really need it" (e.g., learning a new programming language). If memory serves me well that was a sort of "law" or "principle", ironic or not, and I cannot remember its author's name.

Any help in identifying the correct phrase and its author?

Thanks in advance.
