The mathematical notation also lacks a lot of type information. Looking at his example formula, First of all, both x and N are magic variable names, where did t

The mathematical notation also lacks a lot of type information. Looking at his example formula, First of all, both x and N are magic variable names, where did they come from? Second, what happens if x is a string and + is considered string concatenation. Mathematical notation has all the problems of duck typing and even more. In a way that's also the beauty of math, you can multiply matrices with same rules you learned scalar multiplication in 2nd grade. For quick problems where you can keep all variables in your head this is nice to save on typing, but for larger applications you need clearly defined interfaces and a way to encode them.