"It is a genuine scientific challenge to tease out how much of the climate change we see today is due to human activity and how much would have occurred anyway."

"The evidence for a major human contribution is very strong, but is certainly open to discussion."

These two statements stand in stark contrast to the 'settled science' crowd that dominates the narrative and ostracizes the skeptics.  The original point that was made -- there were periods of global warming long before there was human civilization -- is legitimate in the larger discussion of human contribution and has been argued more or less by some of those skeptics who also happen to be top scientists. (Read 'The Deniers' by Lawrence Solomon.)

Parables are, by their nature, overly simplistic and often used to 'dumb down' matters of import for the un- and under-educated masses.  It's use here is superfluous when a simple statement will do, and borders on condescension.  Similar tactics are often used by the 'science' crowd.