This is a course in growth theory, which means it is a course about coherent mathematical formalizations of how some people think economic growth has come around. There are too many theories, though, and most of them have little to do with anything we have ever observed in human history. Some theories are elegant and parsimonious, even beautiful, but they belong to the science fiction section: they talk about the economic growth that could have possibly happened on some planet, but did not happen on ours. One should learn about their existence, and make a memo to never again walk along those paths to try understanding economic growth on planet Earth. Other theories, e.g. those assuming exogenous growth, are really not theories but useful accounting frameworks from where one should start asking the modeling questions.
The course is structured along a "history of economic thought" line: it begins with the classical economists (Ricardo, Malthus and Marx) as they had theories about the necessary absence of economic growth in the long run, and it ends with the current theories about increasing returns, widespread externalities and the weightless economy. The approach is fairly rigorous, but it assumes that participants read the original articles/books and go through the proofs themselves. As we go along we try to separate good theories from bad theories and, more important, we try to separate theories from models, the latter being theories that have some qualitative and quantitative consistency with observed facts. It is models, at the end, that we want to learn about.