It happened again. Someone has sent an e-mail message asking you to sign a petition. You believe in the cause, but should you bother? Moreover, should you forward it, burdening others with the same dilemma?

In some ways, it makes sense to be discerning about which petitions you sign. The vast majority do not achieve their goal, and even when one does gather millions of signatures, it’s hard to tell whether it has moved legislators towards action.