Previous reviews can be found starting here through Dr. P's argument against Nature & God, and Fine-Tuning.
Dr. Pigliucci resumes:
Problems with Theism
In general what we are discussing here tonight is the difference between theism and naturalism, and I think the theist has a lot of problems which need to be addressed. One of these problems is that theism makes an unfounded and difficult-to-defend assumption: it assumes that something else exists beyond matter and energy. That might be a reasonable assumption to some people in the audience, in fact I'm sure, to most people in the audience, but think about it. You know that matter and energy exist. You don't know that something else exists beyond that, and therefore the burden of proof is not on me to demonstrate that that something does not exist; it's on Dr. Craig to demonstrate that something else exists, because we all know the matter and energy are here. If you need something else, then we need some evidence for that.
Also, answering whatever question about the origin of the universe, the origin of life, or anything else, "God did it" really is not an answer. It doesn't provide any answer whatsoever; it doesn't have any explanatory power whatsoever. Well, how did God do it, how did it work , why does it work one way and not another? Science is about not just giving an answer. I'm not going tell you that humans evolve, period. I'm going to tell you how, in what times, and what sequence of events actually is involved. There's much more detailed explanation; in fact, it is an explanation. It may not be a perfect explanation, but it is an explanation.
Another problem is what I call the infinite regression problem. Let's even assume that we do need a God or some kind of supernatural entity in order to explain the universe; well, then, the obvious following question is: where does God come from? I never could get an answer to that. And if the answer is that he was always there, that is exactly the same as saying that matter and energy were always there. There is no difference there.
Furthermore, we have already talked about the problem of negative evidence. There is a tendency on the theistic side to pick up on anything that science cannot resolve or cannot explain, at the least at the moment, as a positive evidence for the alternative explanation. That is not the way things work in rational thinking and logical thinking. You have to have your own arguments, positive arguments, to come out with an explanation. You can't just pick on anything that the other party is unable to explain, especially since part on the process of the other side is exactly to come up with explanations one at a time, and some of these explanations might fall because they're not good.
Dr. Pigliucci starts this segment by declaring that the theist position "has a lot of problems", which is true. Again, focusing on the way it's delivered, even on paper, this delivery sounds tentative. Now, it may have had the best effect that he could have hoped for given the circumstances, but it still bugs me. The first paragraph in this section states the case well, but just seems too conciliatory.
Dr. P digresses into an examination of the first cause argument again, then infinite regression, then negative evidence. I have no problem with the individual thoughts he's expressing, just the way they're ordered and delivered.
Dr. Pigliucci on Naturalism:
The Case for Naturalism
Furthermore, I'd like to go on to say that there are very good reasons to trust naturalism. That is the positive side of my argument. First, naturalism has predictive power. There are a lot of things that work. For example, you can switch on the lights, and the lights do come on. The reason for that is because electrons move around and exchange energy. All these things physics has explained very well, so it does work. Can you come up with a similar example of predictive power on the other side? I don't think so.
Furthermore, it works in practice. The reason you guys were able to get a car, for example, to get up here tonight is because technology works. And technology is based on naturalism. If the assumptions of naturalism were not consistent, you wouldn't have a car, you wouldn't have a TV, you wouldn't have a VCR, and all these other amenities of life. Now you might argue that we might be better off without that, but that's a different question.
Dr. Pigliucci waits until these two paragraphs to make a positive case for naturalism. Again, I agree with what he says, but...
Here's a brief re-imagining of the six paragraphs we just read:
"Naturalism relies wholly on things we can examine to describe the world we live in. Space. Time. Matter. Energy. Exactly those things that we can observe, and nothing else. From those real things, we can describe physics, chemistry, biology, all of the sciences, and predict how things behave under certain well-defined conditions. That ability has everyday benefits - it gives us lightbulbs, and delivers electricity to light them up. It allows us to create automobiles and to fuel them with gasoline so they transport you from point A to point B. You are a naturalist. You depend on these things (and many others ure P that were discovered and refined using naturalist approaches)to live your life. Theism, on the other hand, relies on proposing something not seen to achieve effects that are never observed in the world. No one ever sees a god interacting with people - not in the history of mankind. No one ever sees a god healing an amputee. No one ever sees a god performing a feat in the world that isn't better explained by natural cause and effect. Never. Heaven? Hell? Don't see 'em. God? The Devil? Don't see 'em. Ever. Should we wait all of our lives for these things to magically appear In order to validate our hope or belief that they exist? I can't think of a single good reason to do that - to let your life pass you by completely while you anticipate some event that never happens. To anyone. Ever. The case for naturalism is confirmed every day. The case for theism is never confirmed on any day. Ever."
Next time, we'll wrap up Dr. Pigliucci's opening remarks.