Appearances to the mind are of four kinds. Things either are what they appear to be; or they neither are, nor appear to be; or they are, and do not appear to be; or they are not, and yet appear to be. Rightly to aim in all these cases is the wise man's task.
EpictetusIt is the part of an uneducated person to blame others where he himself fares ill; to blame himself is the part of one whose education has begun; to blame neither another nor his own self is the part of one whose education is already complete.
Epictetus