If we look at mathematics, it has been greatly driven by overloading. Extensions of a notion of numbers from natural numbers to integers, to rational numbers, to Gaussian integers, to p-adic numbers, etc, are examples of overloading. One can easily guess things without knowing exact definitions. If I see an expression that uses both addition and multiplication, I assume distributivity. If I see less-than and addition, I assume that if a < b then a + c < b + c (I seldom add uncountable cardinals).
Overloading allows us to carry knowledge from one type to another.