doctrinaire

Theorist who pays no regard to practical considerations, generally a political ideologist. The term is of French origin, and was applied to a group of politicians at the time of the Restoration (1815–30), who desired a constitution in France modelled according to historical principles and the monarchical system in Britain, and were opposed to absolutism as much as to revolutionary principles. The leaders were Pierre Royer-Collard (1763–1845), François Guizot, and the duc de Broglie.