|Obligatory David Silverman meme|
First, Silverman knows next to nothing about cosmology or biology, and in the debates I've seen him in (like his horrible debate with Frank Turek recently) he claims total ignorance on how the universe or life got started. Now I don't expect him to be a genius in either field, heck I'm not, but shrugging your shoulders and basically saying, "I don't know" isn't going to cut it if you're going to fashion yourself as a public face for atheism and make your rounds in the debate circuit. I mean, at least learn a few of the theories out there (e.g. quantum fluctuations as described by physicists like Lawrence Krauss, or learn about the B-theory of time, or RNA world models - something.) You cannot jump in the atheism/theism debate arena and be totally ignorant on cosmology and biology - it's unacceptable. Silverman is making a fool out of himself every time he does so and he's making a fool out of atheism in the process.
Second, Silverman knows next to nothing about ethics and seems to support a kind of total moral nihilism. Then, he accuses the god of the Bible of being evil! As you can imagine he gets called out on this over and over again, and rightly so. He needs to define what he means by "evil" (which is actually quite easy to do - lacking empathy or compassion) and he needs to define what meta-ethical theory he is subscribing to as an alternative to divine command theory. In the debates I've seen of him, Silverman simply just announces that morality is relative and just keeps repeating that over and over again. But relative to what? What ethical theory does he espouse? He offers us nothing! Silverman needs to sit down with a philosopher, someone like Massimo Pigliucci, or maybe A.C. Grayling, and learn a few of the basics about ethics so that he doesn't continue to look like a damn fool and make atheists look bad. Atheism does not entail moral nihilism, but Silverman is doing a great job making it look that way.
That being said, I think his recent speech at the Oxford Union debate, Religion Harms Society, was pretty decent. See below: