Plutarch writes:
The human mind … is a network of countless tensile impulses, and therefore, if handled rationally, it is far more receptive to change than any other instrument, and far more capable of being influenced and moved to fulfil an idea.
“On Socrates’ Personal Deity” [Περί του Σωκράτους δαιμονίου, De Genio Socratis], Moralia VII:46, tr. Robin Waterfield, ed. Ian Kidd, (London: Penguin Books, 1992), p. 337.