Meditations 10:35

A healthy pair of eyes should see everything that can be seen and not say, "No! Too bright!" (which is a symptom of ophthalmia).

A healthy sense of hearing or smell should be prepared for any sound or scent; a healthy stomach should have the same reaction to all foods, as a mill to what it grinds.

So too a healthy mind should be prepared for anything.

The one that keeps saying, "Are my children all right?" or "Everyone must approve of me" is like eyes that can only stand pale colors, or teeth that can handle only mush.