Men are disturbed not by the things which happen, but by the opinions
about the things; for example, death is nothing terrible, for if it
were it would have seemed so to Socrates; for the opinion about death
that it is terrible, is the terrible thing. When then we are impeded,
or disturbed, or grieved, let us never blame others, but ourselves—that
is, our opinions. It is the act of an ill-instructed man to blame
others for his own bad condition; it is the act of one who has begun to
be instructed, to lay the blame on himself; and of one whose
instruction is completed, neither to blame another, nor himself.