The potato paradox is a mathematical calculation that has a counter-intuitive result. The Universal Book of Mathematics states the problem as such: Fred brings home 100 kg of potatoes, which (being purely mathematical potatoes) consist of 99% water (being purely mathematical water). He then leaves them outside overnight so that they consist of 98% water. What is their new weight? Then reveals the answer: The surprising answer is 50 kg. In Quine's classification of paradoxes, the potato paradox is a veridical paradox.