Deranged people amass at water holes

There are a lot of crazy people in the world & the way we know that is in the proliferation of polar bear clubs from China to Europe to the US. Deranged people amass at lakes, rivers, seasides, water holes in freezing temperatures & mid-winter to jump in. It’s observable that many of them are older people. So the questions are raised: is there a health elixir involved that would induce them to jump half-naked into frigid waters? Or does growing old mean getting senile? Or are they just plain nuts!?

These swimmers are in the Vltava River in Prague, Czech Republic. (Photo by Filip Singer/EPA)