4 quotes about effectual follow in order of popularity. Be sure to bookmark and share your favorites!

Reason and free inquiry are the only effectual agents against error.

Thomas Jefferson

Persuasion is often more effectual than force.

Aesop

Why is it that we entertain the belief that for every purpose odd numbers are the most effectual?

Pliny the Elder

There is no defense against adverse fortune which is so effectual as an habitual sense of humor.

Thomas W. Higginson