I want to be progressive without getting both feet off the ground at the same time†a progressive who is prudent.

-Johnson, Lyndon B(aines) also called LBJ
  Interview,16 Mar.

DefinitionöScience is systematized positive knowledge, what has been taken as such in different ages and in different places. TheoremöThe acquisition and systematization of positive knowledge are the only human activities which are truly cumulative and progressive.CorollaryöThe history of science is the only history which can illustrate the progress of mankind. In fact, progress has no definite and unquestionable meaning in other fields than the field of science.

-Sarton, George A
  The Study of the History of Science.

We who are liberal and progressive know that the poor are our equals in every sense except that of being equal to us.

-Trillin, Calvin Marshall
  The Liberal Imagination,'Princess Casamassima'.