[sciyoshi]

Funny, because I think the Wolfram language (also as a long-time user) is actually really well-designed and consistent, and has stood the test of time. Even ignoring the standard library, it has a really expressive syntax for pattern matching and functional programming, and I find that you can often do very complex things with very little code. For doing any kind of symbolic manipulation or lazy evaluation, it's pretty hard to beat.

On the other hand, I feel that his theory of cellular automata as some fundamental underpinning to mathematics is misguided.

[jwr]

Really? I found that it's fine when all your data is lists or matrices, but it becomes increasingly terrible if you want to process structured data. Maps (associative) have been added late and in a half-baked way, using them is a pain. The way macros are written is pretty bad syntax-wise. There seems to be little consistency in terms of which arguments come first, so composing functions into pipelines can be awkward. Variables in "With" and "Module" cannot refer to earlier bindings, so I end up with multiple nested With/Module statements. Also, "Module" for lexical scoping, really?

Also, I never managed to achieve any reasonable degree of code reuse in Mathematica. Most of my notebooks are single-purpose.