Xenos Parodox is a famous enigma that says if a runner in a race kept going halfway to the finish line, he would never cross it. But if you divide any number over and over, wouldn't you eventually arrive at irrational numbers like pi or .33333...? Meaning Xeno's Parodox is just an unworkable exercize, because you would eventually come across numbers you couldn't divide by two and get a finite result. So a runner in the experiment would have to go a little more or a little less than halfway to the finnish line. So it isn't a parodox, but an unworkable experiment.