What might make it IMPOSSIBLE for a person to keep a secret?

Epictetus asserts that the keeping of a secret is the most obvious exercise of free choice, since the choice of whether to reveal the secret is…

Epictetus asserts that the keeping of a secret is the most obvious exercise of free choice, since the choice of whether to reveal the secret is clearly within your power. Another person can imprison you, of course, if you will not tell, and even kill you, but no one can make you reveal the secret.2. What might make it IMPOSSIBLE for a person to keep a secret? (You may consider historical examples in your answer to this question.)