Response to a climate denier who was smart enough to have noticed that our raw CO2 number is low compared with pre-history

And now to the erudite sounding numbers you posted. As you pointed out, absolute CO2 levels are a poor predicted of global temperature. But, all virtually all CO2 peaks in history are capped by mass extinction events, and virtually all mass extinction events occur at CO2 peaks. And much, much more importantly, CO2 levels are changing now 25,000 times faster that at any other point in the geologic record: http://www.johnenglander.net/co2-levels-and-mass-extinction-events/
Couple that with the way recent temperature trends are precisely predicted by the same anthropogenic carbon emission climate models that predict losing most coastal cities this century and large sections of the most densely populated and poorest parts of the planet becoming uninhabitable without first world technology we have no political will or logistical ability to provide to the billions who will need it, and you get a probability graph with a tiny little corner that represents your “likely do nothing just enslave more people” scenario, and the “doomsday” scenarios you deride which drove the Paris accords are actually a hopeful little chunk of probability on the mild side of the curve that presumes that climate accords will work, bombs won’t irradiate the biosphere, oil stockpiles won’t get burned en-masse in scorched-earth rear guard actions during resource wars, the ocean won’t go anoxic producing massive methane plumes-30x more effective at boiling us than CO2, the fresh water balance change when the ice caps melt won’t screw up global weather patterns to the point where no plants are growing in the right zones anymore, rainforests and blue-green algae won’t die off, releasing their sequestered carbon as both CO2 and methane and halting the primary extant sequestration path. In short, your comment that the world’s climate is complex is valid, but your conclusion that this means we should just keep spinning all these dials of a machine we are only just beginning to comprehend is profoundly shortsighted, selfish and illogical. Your argument that current political and economic disruption from simply being less voraciously greedy for a little while to let the dust settle and suss things out utterly fails to recognize just how many orders of magnitude worse that sort of political overreach and infringement of personal liberties get when people are dying of famine, war, weather, and the myriad other calamities that are already unavoidable, but are still mitigatable if we act fast. Really fast.