“We hear only half of what is said to us, understand only half of that, believe only half of that, and remember only half of that.”

"The System of Doctor Tarr and Professor Fether" (1845)

A Thousand & One Epigrams: Selected from the Writings of Elbert Hubbard (1911)

Original: (de) Ein Philosoph, der keine Beziehung zur Geometrie hat, ist nur ein halber Philosoph, und ein Mathematiker, der keine philosophische Ader hat, ist nur ein halber Mathematiker.

Gottlob Frege: Erkenntnisquellen der Mathematik und der mathematischen Naturwissenschaften, 1924/1925, submitted to Wissenschaftliche Grundlagen; posthumously published in: Frege, Gottlob: Nachgelassene Schriften und Wissenschaftlicher Briefwechsel. Felix Meiner Verlag, 1990, p. 293

Source: Dreaming the Dark: Magic, Sex and Politics (1982), Ch. 6 : Building Community : Processes for Groups, p. 92
Context: We are all longing to go home to some place we have never been — a place half-remembered and half-envisioned we can only catch glimpses of from time to time. Community. Somewhere, there are people to whom we can speak with passion without having the words catch in our throats. Somewhere a circle of hands will open to receive us, eyes will light up as we enter, voices will celebrate with us whenever we come into our own power. Community means strength that joins our strength to do the work that needs to be done. Arms to hold us when we falter. A circle of healing. A circle of friends. Someplace where we can be free.

#465
Vectors: Aphorisms and Ten Second Essays (2001)

Source: Hold Me Closer: The Tiny Cooper Story

Socrates in Plato's Republic talking about women lacking rights. As quoted by Bettany Hughes: "Feminism started with the Buddha and Confucius 25 centuries ago" http://www.telegraph.co.uk/women/womens-life/11785181/Feminism-started-with-the-Buddha-and-Confucius-25-centuries-ago.html.
Attributed

Les silences du colonel Bramble (The Silence of Colonel Bramble)

As quoted in The New York Times (2 July 1978)