Following up on Noah Smith’s marvellous definition of derp, I thought I would add the first person to give the declension of this irregular verb
* I can’t see this happening
* You regularly restate your tight (low probability) prior
* He herped a flerp of derp, the twerp
The classic example, cited by Noah is that of people whose view that solar photovoltaics can never work has been unshaken by a decade of massive cost reductions and growth in installations (estimated at 55 GW this year, and predicted to exceed 100 GW in the near future). Even more important though, is the belief in market liberalism held by most people whose views were formed between 1975 and 1995, and haven’t been affected by the disasters of the subsequent two decades.