Really? I'm getting kind of tired of the tool analogies. They are thrown around as answers in place of actual thinking and reasoned arguments. The comparison between learning how to use a torque wrench and learning a language is absurd.

It depends.

Learning a significantly different language can be mind-expanding. Going from C to Lisp is not just picking up a different tool. More like a brain transplant.

Going from Java to C# is more ho-hum. There will be no epiphanies. More like "Oh, Microsoft solved problem X. That's nice."

That really is like replacing a Husky brand wrench with a Craftsman brand wrench.