 Given any two true sentences A and B, the conditional “If A, then B” is true. For example, provided it is true that the sun is made of gas and also true that elephants have four legs, then the truth-functional conditional “If elephants have four legs, then the sun is made of gas” is also true. However, the gaseous nature of the sun would not normally be regarded as either a conceptually, or even a contingently, necessary condition of the quadripedality of elephants. Indeed, according to the standard theory, any truth will be a necessary condition for the truth of every statement whatsoever, and any falsehood will be a sufficient condition for the truth of any statement we care to consider.