Evolved Minds

What do irrationality, superstition and math have to do with each other? Suppose you take a test for a certain uncommon form of cancer. One that affects one person in ten thousand and you get a positive result for the cancer using a test that is 98 percent reliable. What are the chances that you have that cancer? Well if you figured you are doomed instead of knowing statistically that your chances of having the disease is less than half a percent, You could use a bush up on your arithmetic and Ronald de Sousa can help.