What we know vs. suspect with respect to climate change

All other things being equal, it is certain that CO2 results in temperature increase... at least until other potential feedback kicks in.

I'm just not convinced that the earth's climate is in an unstable equilibrium: I imagine a system as complex as the earth could only have remained (relatively) stable over millions of years through the existence of feedback factors we don't yet understand. I also find it hard to believe that the amount of CO2 in the atmosphere has more to do with widespread, large-scale temperature changes than the energy output of the sun, which fluctuates by as much as 10% every 10,000 years.

That said, I'm no climatologist. It's possible the CO2 change caused by man has a measurable effect, and that effect may well be negative given the other factors affecting the climate right now. It's indisputable, however, that the earth undergoes much wider swings in climate than that which we could possibly cause with our own activity, and killing our economies and sacrificing personal freedom for the relatively benign short-term damage that might be caused by human activity is foolish.