 Jane Addams, John Dewey, and George Herbert Mead developed their philosophies as all three became friends, influenced each other, and were engaged in the Hull-House experience and women's rights causes.In the 1908 essay "The Thirteen Pragmatisms", Arthur Oncken Lovejoy argued that there's significant ambiguity in the notion of the effects of the "truth" of a proposition and those of "belief" in a proposition in order to highlight that many pragmatists had failed to recognize that distinction.He identified thirteen different philosophical positions that were each labeled pragmatism.