Pierre Hadot (1922-2010), Philosophy as a Way of Life: Spiritual Exercises from Socrates to Foucault
, tr. Michael Chase (Oxford: Blackwell Publishers, 1995; rpt. 1999), p. 62:
True education is always oral because only the spoken word makes dialogue possible, that is, it makes it possible for the disciple to discover the truth himself amid the interplay of questions and answers and also for the master to adapt his teaching to the needs of the disciple. A number of philosophers, and not the least among them, did not wish to write, thinking, as did Plato and without doubt correctly, that what is inscribed in the soul by the spoken word is more real and lasting than letters drawn on papyrus or parchment.
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