Sincerity and goodness ought to have their own unmistakable odour, so that one who encounters this becomes straightway aware of it despite himself. A candour affected is a dagger concealed. The feigned friendship of the wolf is the most contemptible of all, and to be shunned beyond everything. A man who is truly good and sincere and well-meaning will show it by his looks, and no one can fail to see it.
Marcus Aurelius (AD 120 – 180), Meditations