For a start, my name's not Clyde, it's Vincent. It's in my username. Thought you'd've figured that out. Second, it's an argument about why letting a bunch of individuals who have no incentive to care what happens to the group go wild with no previously-agreed-upon restrictions about how much they should use is bad, and that's not true of any socialist movements I'm aware of. Thirdly, the photo on the Wikipedia page for tragedy of the commons is of pollution.