The third major contribution of De l'esprit des lois was to the field of political sociology, which Montesquieu is often credited with more or less inventing. The bulk of the treatise, in fact, concerns how geography and climate interact with particular cultures to produce the Spirit of a people. This Spirit, in turn, inclines that people toward certain sorts of political and social Institutions, and away from others. Laws and Customs are Institutions that derive their normative nature from the relationships and the way of life established between humans within each Society.
