Yet another mass shooting (and stabbing)The Santa Barbra killings recently have predictably reinvigorated the anti-gun nuts. I somehow missed the companion call for the registration and/or banning of knives, since half of the number killed were stabbed to death. I have just formed a group called People United.Knives Eradicated. (PUKE). Follow us at www.puke.org. Are you with me? Good. Now, we can finally look to scientific research about the causes of these insane events. Below is a chart documenting the causes of mass shootings.