There was once the land of the Foo. They were an awful dirty filthy bunch. If any outsiders came near, the Foo would attack them, not with spear or sword, but with their poisonous feces, the poison of which was activated when wiped. When outsiders came near and were hit with Foo sh*t, they'd wipe it off, which would activate the poison and then kill them. Then one leader of outsiders came up with an idea: He told his band about the Foo, about their poisonous feces, and that it would only kill them if the wiped it off. This leader then gave a command to his band: "If the Foo sh*ts, wear it."