Other people’s views and troubles can be contagious. Don’t sabotage yourself by unwittingly adopting negative, unproductive attitudes through your associations with others.

This quote is frequently attributed to Epictetus, e.g. by Brigid Delaney, Six ways to make your life easier and more peaceful – by using stoic principles, The Guardian, 22 November 2023. This quotation originates from the 1995 book: The Art of Living: the classic manual on virtue, happiness, and effectiveness, page 23, by Sharon Lebell, a book which "interprets" Epictetus.