I don't know what the larger context of the quote it, but as commented by others, it can certainly be taken out of context as support of a nerd-superiority complex.

That aside, the nature of the "soft sciences" is that you can't very well conduct controlled experiments, because it is unethical, or it is hard to control all the variables. So current soft sciences plod about trying to gather some type of predictablity in their theories, but often falling back to trying to make causal statements of their experimental observations.

I think there's been attempts before, like cybernetics, that tries to model human behavior using signal processing techniques. To my understanding, it's since fallen out of favor. So while it's been tried before--and I don't know for sure, but my gut says that there probably is mathematics, other than statistics, to bring more analysis into the social sciences.

Otherwise, the math just hasn't been invented yet. Currently there are studies in nonlinear systems, complex systems, and math of intervation and manipulation. My shallowly informed guess is that one of these will help out.

Or else we just have to wait for a Physicist to help us out here.