Seneca said this quote

“ In truth, Serenus, I have for a long time been silently asking myself to what I should liken such a condition of mind, and I can find nothing that so closely approaches it as the state of those who, after being released from a long and serious illness, are sometimes touched with fits of fever and slight disorders, and, freed from the last traces of them, are nevertheless disquieted with mistrust, and, though now quite well, stretch out their wrist to a physician and complain unjustly of any trace of heat in their body. It is not, Serenus, that these are not quite well in body, but that they are not quite used to being well; just as even a tranquil sea will show some ripple, particularly when it has just subsided after a storm. What you need, therefore, is not any of those harsher measures which we have already left behind, the necessity of opposing yourself at this point, of being angry with yourself at that, of sternly urging yourself on at another, but that which comes last -confidence in yourself and the belief that you are on the right path, and have not been led astray by the many cross- tracks of those who are roaming in every direction, some of whom are wandering very near the path itself. But what you desire is something great and supreme and very near to being a god - to be unshaken. ”