Anything, any idea, if viewed from one particular angle, in one particular context can be its opposite. Good can be bad. Complete nonsense can be great wisdom, and sensibility can be totally meaningless. Liberal democrats call for military action. Right-wingers want to legalize drugs. In death there is life, as there are lives of nonexistance. Just hold any idea at arms length, tilt it at various angles, squint and suddenly, BINGO, everything is reversed. If you can't see a reversal of some belief you hold sacred, your arms are not long enough.