I think, Socrates then Cicero exaggerated things a big deal when they said
All silly people were unsound
But I go ahead of myself.
Sound here means minds that are under no perturbation from any motion as if it were a disease and unsound are those that are differently affected.
It’s this statement by Cicero in his disputations that I think is a stretch. He writes
No fool is ever free from perturbations of the soul; but all that are diseased are unsound; and the minds of all fools are diseased; therefore all fools are mad.
He says elsewhere that grief, being a disorder of the mind, cannot afflict the wise. This he writes is because, the man of courage is the only wise man and as such, grief cannot befall him.
