So, What Actually Is 'Mathematically Impossible'?

Sen. Hillary Clinton

Sen. Hillary Clinton at a fundraiser in New York, on Mother's Day. Joe Raedle/Getty Images hide caption

itoggle caption Joe Raedle/Getty Images

When pundits say it's a "mathematical impossibility" for Sen. Hillary Clinton to win the Democratic nomination for president, they're wrong. Bryant Park Project producer Ian Chillag explores an over- and misused term with a very precise meaning and few good examples.

Chillag speaks to a physicist in central Florida who figured out at least one impossibility: vampires. The bloodthirsty beings, in theory at least, spread exponentially, so the physicist asks Chillag to imagine a population with one vampire and 10 humans. That one vampire bites the human, then there are two vampires and eight humans. The next night it's four vampires and six humans, then eight vampires and two humans. If in the year 1600, the physicist tells Chillag, there were one vampire and 500 million humans on Earth, "in two and a half years, all the population on Earth becomes a vampire."

In other words, Chillag concludes, either we are all vampires, or there are no vampires — making vampires an authentic impossibility.

As for Clinton's chances at immortality? That remains, it must be said, a possibility no mathematician can yet deny.



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