But though it cannot be reasonable not to gain happiness for fear of losing it, yet it must be confessed, that in proportion to the pleasure of possession, will be for some time our sorrow for the loss.
Scientists tend to focus on what they don't know more than what they do know. And there are a lot of things we still don't know about the climate. But we know the difference between climate variability and climate change, and right now the amount of carbon in the atmosphere is well outside the variability pattern - and that's quite quantifiable.