… is from pages 115-116 of Julian Simon’s posthumously published 1999 volume, Hoodwinking the Nation  (footnote excluded):
We cannot be certain what the future holds. But we do know the results of similar prophesies in the past. The doomsaying prophets of the 1960s and 1970s – the same people who are the false prophets of today – were wrong across the board. And prophets in previous eras also have a very poor record.
We also have irrefutable evidence that the assertions of fact on which the doomsters supposedly base their prophesies are false. They say that our air and our water have been getting dirtier in recent decades, and that natural resources have been becoming more scarce in past decades and centuries. These propositions are demonstrably, indubitably wrong. There is every reason to believe that the current environmental prophecy of doom is wrong.