As I understand his argument:

1) It was hotter in the past when humans weren't burning as much stuff as now.

2) It was hotter in the past when there weren't any humans(, at least if you believe the scientists and not what the Bible says).

3) Scientists and politicians want to tax everyone, reward their cronies, get rich, punish their enemies, make the people poor, prevent the truth from getting out, and destroy capitalism for ideological reasons. See "None Dare Call it Conspiracy" for the details. Don't believe stuff you may read about "tragedy of the commons" or "pricing externalities" or "the cost of protecting oil in the Persian gulf".

4) Humans have only changed the CO2 concentration a tiny amount (~ 150 ppm) since industrialization. Elementary logic tells us that small things don't matter.

5) Computer models are always wrong in the details, therefore the climate models are wrong.

6) It was cold somewhere last week, therefore the IPCC and James Hansen are wrong.

7) Some website run by someone with a degree in a scientific topic said that it found a mistake in a paper written by world experts on Earth's climate, therefore the paper is wrong and therefore anthropogenic climate change is wrong. He can't get his rebuttal published because of the conspiracy mentioned in #3.

8) Someone on a mailing list said they were working a "trick" to "hide the decline" - proof that "climate change" is conspiracy just like he said.

9) People who devote their lives to researching a topic are suspect - they're too self-interested in finding the "correct" result. That's why it's important that lay-people with no training or expertise in the topic are treated as better authorities. Similarly, when one has asbestos in one's house and needs to do renovations that disturb it, it's important to hire a couple of guys from the Geeks Squad to do the repairs because experts in asbestos abatement are too self-interested.

10) Burning trees is exactly the same as burning oil and coal that were laid down millions of years ago. There's no way to tell them apart, therefore one can't point to evidence of changes in the isotopes in the atmosphere to prove anything. The rate of change in burning oil and coal and burning wood over the last 200 years doesn't mean anything either. The Earth is a big place and nothing humans do make much difference.

11) Soot particles and SO4(2-) ions will save us. Acid raid wasn't a big deal. Lung cancer and respiratory disease isn't a big deal. The "killer fog of '52" was a hoax. Volcanoes will save us.

12) The sun changes over time, the Earth's orbit has changed over time, etc. And yet there have been ice ages and warm periods. What's a couple of degrees increase in 100 years, and more in the next hundred years? Who cares if that's an eye-blink in the Earth's history? Who cares if it will cost trillions of dollars to move cities away from the coasts, that prime farmland is being destroyed, that many food crops cannot tolerate elevated temperatures overnight, that animals are being forced to rapidly move large areas as their habitat changes, that some animals require cold in part of their life cycle? It's no big deal - just scare mongering. And besides, we can't do anything about it anyway, not if I want to have the Freedom(® Tea Party) to drive my F-350 to work every day, and if oil and coal companies are to continue to dominate total employment in the world[*].

13) Algore is fat.

Therefore, anthropogenic climate change is wrong and a hoax. ;-)

HTH.

Cheers,
Scott.
[*] ~ 6.5 million total coal and oil jobs in the world, according to this: http://www.greenpeac...-jobs-to-2030.pdf