“The greatest deception men suffer is from their own opinions.”– Leonardo da Vinci Related Quotes “The real use of gunpowder is to make all men tall.”– Thomas Carlyle “Men feel that cruelty to the poor is a kind of cruelty to animals. They never feel that it is an injustice to equals nay it is treachery to comrades.”– Gilbert K. Chesterton “Things that I felt absolutely sure of but a few years ago, I do not believe now. This thought makes me see more clearly how foolish it would be to expect all men to agree with me.”– Jim Rohn