“Liberalismus (1) Politischer Liberalismus.” Handwörterbuch der Sozialwissenschaften 6 (Stuttgart-Tübingen-Göttingen, 1959).

Excerpt:

The term is now used with a variety of meanings which have little in common beyond describing an openness to new ideas, including some which are directly opposed to those which are originally designated  by it during the 19th and the earlier parts of the 20th century’s. What’s will alone be considered here is that broad stream of political ideals which during that period under the name of liberalism operated as one of the most influential intellectual forces guiding developments in Western and Central Europe. This movement derives, however, from two distinct sources, and the two traditions which they gave rise, though generally mixed to various degrees, coexisted only in an uneasy partnership and must be clearly distinguished if the development of the liberal movement is to be understood.”

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