“Any question of philosophy … which is so obscure and uncertain, that human reason can reach no fixed determination with regard to it; if it should be treated at all; seems to lead us naturally into the style of dialogue and conversation.”
Pamphilus to Hermippus, Prologue
Dialogues Concerning Natural Religion (1779)
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David Hume 138
Scottish philosopher, economist, and historian 1711–1776Related quotes

Rules for the Direction of the Mind in Key Philosophical Writings (1997), pp. 29-30 http://books.google.com/books?id=jjWPe-9NPoEC&pg=PA29

Eighth Thesis
Idea for a Universal History from a Cosmopolitan Point of View (1784)

Source: 1930s, Power: A New Social Analysis (1938), Ch. 16: Power philosophies

Attributed in American Quotations (1992) by Gorton Carruth and Eugene H. Ehrlich, p. 149
1990s

Encyclical Fides et Ratio, 14 September 1998
Source: www.vatican.va http://www.vatican.va/holy_father/john_paul_ii/encyclicals/documents/hf_jp-ii_enc_14091998_fides-et-ratio_en.html

An Essay in Defence of the Female Sex. P. 54 https://archive.org/details/essayindefenceof00aste