Robert Johnson and I have been discussing the extent to which economics is a science (or a "soft science") in the comment section of this post. The very term "soft science" is like nails on a chalk-board to me. I find it completely vacuous. I'll loudly proclaim that there are varying complexities of the systems that various scientists study and that this needs to be taken seriously - but this doesn't really speak to the scientific quality of that field of study. Social science is not the half-way point between the "sciences" and the "humanities". "Social science" is the name we give to certain sciences because our self-absorption and self-aggrandizement revolts against the idea of classifying economics as a sub-branch of primatology.
Anyway - I can't really comment much longer on that post, but at the end I was getting the sense that a lot of the difference between my views and Robert's views might be emerging from the fact that I separate questions of science, engineering, and forecasting. To me they are very different things. One is the pursuit of understanding through the scientific method. Another is the application of that understanding to problem solving. The third is the application of that understanding to piercing through the "dark forces of time and ignorance that envelope our future". All are noble pursuits. All are rightfully done by economists with varying degrees of success. All are quite distinct, though. I think we are quite good at economic science, and somewhat less good at economic engineering and forecasting (we are probably better at engineering and forecasting than meteorologists, worse at engineering but better at forecasting than geneticists, and worse at both engineering and forecasting than astronomers).
Anyway - all I intended to do here was to quickly point readers to an essay that Greg Mankiw wrote a while back on the macroeconomist as an engineer and the macroeconomist as a scientist. Here's a good selection from the beginning:
"To avoid any confusion, I should say at the outset that the story I tell is not one of good guys and bad guys. Neither scientists nor engineers have a claim to greater virtue. The story is also not one of deep thinkers and simple-minded plumbers. Science professors are typically no better at solving engineering problems than engineering professors are at solving scientific problems. In both fields, cutting-edge problems are hard problems, as well as intellectually challenging ones. Just as the world needs both scientists and engineers, it needs macroeconomists of both mindsets. But I believe that the discipline would advance more smoothly and fruitfully if macroeconomists always kept in mind that their field has a dual role."