Sincerity: Cross My Heart and Hope to Die

From the Unknowable Truth Glossary

Sincerity, according to Google’s expression of Oxford Languages, is “the quality of being free from pretense, deceit, or hypocrisy.”

Sincerity is akin to “honesty,” and when we sense someone is sincere, we’re likely to take them at their word—but that doesn’t mean what the person is saying is true. Someone can sincerely state a proposition they believe to be true, but they might be honestly mistaken. It means a statement can be both sincere and wrong.

It also opens up the possibility that a person can be insincere, but also correct, crossing into the realm of irony, satire, and paradox. Worryingly, some liars and conmen feign sincerity to gain their marks’ trust.

In his book Why We Lie, David Livingstone Smith suggests that deception is so favorable to survival that humans have evolved to deceive themselves to better convey deceptions, making “sincerity” a troublesome measure of truth.

This is all true to my knowledge. Cross my heart and hope to die. I write more about Why We Lie on my sister publication Advocate Craft.