>MIKE OSSIPOFF wrote: > > > I still haven't heard anyone actually say what the mathematical > > definiton of "if" is. Will it be in a definition of mathematics? > > Won't someone tell me what it is? > >I don't know about the word "if" being defined in math except that it's >usage is the same as in logic. But I think logic actually just defines >implication (or inference). "If A then B" is understood as an equivalent >way of saying "A implies B". > >Implication is defined as a logical expression which is true if the >consequent (B) is true for all cases in which the antecedent (A) >is true. That definition doesn't come from a textbook but I think >it's fairly close. That sounds the same as the definition that I posted. Martin appears to have been mistaken in his claim that my meaning for "if" is different from that of mathematicians. Maybe it's better to say that (If A then B) is true if B is true in all cases in which A is true, rather than saying that (If A then B) means that A being true means that B is certain to be true. But the meaning is the same. You were wrong about my using a different meaning for "if", Martin. p.s. My probability definition might need a little touch-up modification. I wrote it hurriedly late at night. Mike _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com
