1. When words are about to be spoken in anger and might be regretted.

2. When it has been said before and is not worth repeating.

3. To justify one's behaviour, of which one is not proud, by citing someone else's.

4. To avoid inflicting unconstructive criticism.

5. When silence resonates and words are empty.

6. When honourable actions are more expressive than words.

7. After indicating graciously that the question oversteps one's boundaries.

8. When the moment is perfect without words.

9. When the heart is full and speaking would be a drain.

10. When to speak would only be to boast.