The key thing is "Notation as a tool of thought" What would mathematics or music be without notation? It might be hard to believe but there was once a time

The key thing is "Notation as a tool of thought" What would mathematics or music be without notation? It might be hard to believe but there was once a time mathematics didn't have notation for "+, - * /" or even the decimal point "." Mathematics was solved by writing words, it was slow, it was painful and it didn't progress as fast. Likewise with music, sure we can write music by writing do re mi fa so la ti, but really? Yet, this is how we program today with words, writing english words that don't mean what they claim to be. SomethingManager, SomethingDelegator, etc. Bah! The very ideal behind APL is to notations, to represent code with symbols which are non ambiguous and always mean the same thing. There's a lot that we have lost. It's still worth taking a look at. For those interested, J (www.jsoftware.com) is a free version with lots of great learning resources.