Meanings of mental unsoundness in English

Greek writers speak of cases of mental unsoundness as occurring with some frequency in Greece.

The inhabitants of the Roman Empire were afflicted with mental unsoundness and Nero was considered crazy.

It's a wonder you didn't think of upsetting his will on the ground of mental unsoundness.

Some phase of mental unsoundness is produced by any of the drugs which affect the nerves, whether stimulants or narcotics.

If this sort of mental unsoundness did not justify subjects in withdrawing their obedience from princes, the plan of a Regency was evidently indefensible.

How these reached us I do not know; but of course, as soon as their mental unsoundness was ascertained, they were placed in asylums.'