> As a result, the five million lines of Mathematica code that make up Wolfram|Alpha are equivalent to many tens of millions of lines of code in a lower-level language like C, Java, or Python.

Calling Python a "lower level language" seems quite a bold statement. It makes me want to learn Mathematica just for the sake of understanding why it is higher level than Python.

I think it is considered higher level just for the sake of how much work is already done for you similar to a program like matlab with many many already compiled functions and algorithms. It probably isn't so much higher than python when you take into account all the available libraries however it is probably much faster at these tasks.