No, he did not consider things that have never happened before.
He can only extrapolate from events that already happened. Human made global warming is a first time, so difficult to say what will happen from a historical perspective.
Human-made global warming appears to go back to the advent of agriculture, though, so for all intents and purposes it has been a constant throughout the history of which we speak.
He can only extrapolate from events that already happened. Human made global warming is a first time, so difficult to say what will happen from a historical perspective.