We offer a theoretical approach to federalism by defining a theoretical approach as a general account of the subject. It is general in that it applies in any political situation, at any time in history when political entities that are recognizable as nations existed. It is an account in being a...

Recent study of the history of technological change has provided better understanding of the driving forces for technological innovation, as well as quantitative estimates of historical rates of technical change. Although such results are widely used in long-term energy models to estimate future...