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Correlation does not necessarily imply causality. In fact, it is just as reasonable to conclude that warm periods result in increases in greenhouse gases rather than the other way around.

Of course.

But also you realize, of course, that such a view does nothing to contradict the idea that carbon dioxide could be leading to global warming....right?

After all, it's not like we have an example from the past in which man pumped CO₂ into the atmosphere at our current rate, raising the atmospheric concentration to its current level (that is, raising it above the quasiequilibrium level and potentially making CO₂ become a forcing element, not reactive). It's not like Homo erectus was buring THAT much stuff, even after discovering fire! :-)

Additionally, the temperature increase could very well have been the result of feedbacks, following initiation by a change in insolation.

After all, it's not like we have an example from the past in which man pumped CO2 into the atmosphere at our current rate, raising the atmospheric concentration to its current level (that is, raising it above the quasiequilibrium level and potentially making CO2 become a forcing element, not reactive).

The best natural analogue, well out of reach of ice core but not oceanic sediment cores, is the Paleocene-Eocene Thermal Maximum. It occurred over much longer time-scales, but it did show the expected cause-and-effect relationship.

such a view does nothing to contradict the idea that carbon dioxide could be leading to global warming....right? After all, it's not like we have an example from the past in which man pumped CO2 into the atmosphere at our current rate...

Oh, no? There were at least two prior times in the geologic record (450 million and ~180 million) when CO2 levels were over ten times what they are now and they were both during major cold spells. (the top graph shows CO2 concentrations, the bottom, temperatures)

"The above chart shows the range of global temperature through the last 500 million years. There is no statistical correlation between the level of carbon dioxide in the atmosphere through the last 500 million years and the temperature record in this interval. In fact, one of the highest levels of carbon dioxide concentration occurred during a major ice age that occurred about 450 million years ago. Carbon dioxide concentrations at that time were about 15 times higher than at present.":
http://www.tcsdaily.com/article.aspx?id=010405M