The latter is the one most use. The former is acceptable, but it is also used as the symbol of sports teams whose emblem has horns (hook 'em horns) and in Hawaii, meaning "Just Hang Loose".
"Consensus is the absence of leadership." Margaret Thatcher
"I'm fascinated with how primitive the human mind still is. It can be misdirected so easily." John Gaughan
"Success is uncommon. Therefore, not to be enjoyed by the common man." Cal Stoll