The first of all virtues is innocence; the next is modesty. If we banish modesty out of the world, she carries away with her half the virtue that is in it.

Modesty does more work than it gets credit for. A great deal of restraint depends on not wanting to be seen doing the thing, and when the sense of shame goes, the behaviour it was quietly holding back goes with it. That is what is meant by half of virtue leaving in its company. Whether every old propriety deserved keeping is a fair question, and the mechanism still holds.

Notice what you would not do if the people you respect could see it. That flinch is worth listening to rather than arguing away, at least until you have a better reason than convenience.