When asked why the subject of economics is not a science then its exponent adopts a kindly look — as though the questioner is not as bright as he himself is — and answers along a line that goes something like this:
“Well . . . you see, economics is not just about making things, moving them about and then selling them in a voluntary exchange with a customer, it is also inextricably mixed up with a complex creature shot through with phobias, powerful instincts, sudden changes of mind and, often, full-scale panics. One half of the subject is beyond computation and we can do little about it.”
If you then try to explain that there’s quite a raft of scientific disciplines investigating human nature and that they’re all, from different angles, defining humans pretty accurately, then a distant view appears in the economist’s eyes, his fingers start drumming and you know that, once again, you haven’t quite got through.