Well just like what Cmunt87 said, he had died back in 2012 in February. I'm taking a guess and saying that it was probably complications brought on from whatever illness he had. Supposedly it was maybe Apert Syndrome or Crouzon Syndrome, but there is no real way to say what he had.
Locke believed in a state of nature( no government) people would be unsafe and no one would be peaceful to each other. Hobbes was the opposite of that and believed everyone would help one another and be kind.