SICP says "Program == Language Evaluator" What does this  mean?
jacquesm: The input data would be considered to be 'in' the language.Think of the evaluator as a classic unix 'filter', the language it implements describes how the input should be formatted.Just like when you write 'english', you expect the processor of your 'output' to be able to evaluate the english language so that it can produce meaningful output from your input.I think it is as simple as that. But if it isn't I'm sure it won't be long before I'm corrected ;)edited slightly for clarity (added the 'to be in' in the first sentence)