Men are disturbed, not by things, but by the principles and notions which they form concerning things.
 Epictetus, Enchiridion (125). copy citation

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Author Epictetus
Source Enchiridion
Topic principles concern
Date 125
Language English
Reference
Note Translated by Elizabeth Carter
Weblink http://classics.mit.edu/Epictetus/epicench.html

Context

“For thus, if any hindrance arises in bathing, you will have it ready to say, "It was not only to bathe that I desired, but to keep my mind in a state conformable to nature; and I will not keep it if I am bothered at things that happen. 5. Men are disturbed, not by things, but by the principles and notions which they form concerning things. Death, for instance, is not terrible, else it would have appeared so to Socrates. But the terror consists in our notion of death that it is terrible. When therefore we are hindered, or disturbed, or grieved, let us never attribute it to others, but to ourselves;” source