Full Idea
Plutarch says if you have mastered principles then logos will silence your desires like a master silencing a dog - in which case the logos functions without intervention on your part - you have become the logos, or the logos has become you.
Clarification
'Logos' is the broad Greek concept of human reasoning
Gist of Idea
When logos controls our desires, we have actually become the logos
Source
Michel Foucault (Ethics of the Concern for Self as Freedom [1984], p.286)
Book Reference
Foucault,Michel: 'Essential Works 1954-1984 I: Ethics', ed/tr. Rabinow,Paul [Penguin 1994], p.286
A Reaction
If you believe that logos is pure reason, you might be quite happy with this, but if you thought it was a cultural construct, you might feel that you had been cunningly enslaved. If I ask 'what is 7+6?', logos interrupts me to give the answer.