still, many of the greatest thinkers, from pythagoras to galileo, even the great gauss refused to tackle it, deeming infinity to be "unthinkable." but believe it or not, the idea of infinity begins with something as simple as counting and the way in which we measure the world. as humans, we find hints of infinity as soon as we learn to count. once we run out of fingers, we realize there might be a never-ending number of things, from the grains of sand on planet earth to the stars in the heavens. faced with orders of magnitude beyond what our human senses can comprehend, many great minds have concluded that infinity is outside the purview of mathematics and best left to philosophers and theologians. in fact, the subject has been taboo for mathematicians throughout much of history -- perhaps most especially the ancient greeks -- because it seemed to pose a problem that could not be solved. zeno of elea, who predated aristotle, wrote a series of paradoxes that still give us pause today. one of the best known tells the story of achilles and the tortoise and their race. achilles is such a fas