“But Credentials”

Credentials bolster authority. Attacking credentials undermines authority. Both can be read as ad hominem arguments. Life is simpler with attacks or appeals to authority.

This square may be implied by #ButMyGuru, and #ButScapegoat.


What’s your background? Shiva is an MIT pHD. What are you?

(Calgary, defending the inventor of Email)

[A]s a life-long life-scientist I know that even at 410 ppm CO2 is too low for maximum plant growth, and that it is entirely beneficial for life.

(Patrick, who worked all his life as a PR guy for various industries)

Objections and Replies

Climate scientist. This person isn’t a climate scientist—
Publishing climate science papers ought to be good enough.

Expertise. There are different kinds of expertise—
☞ Sounds like special pleading to me.

Scientist. I am a scientist and—
☞ Where’s your work on climate science?

Studies. This person has not studied this or that—
☞ Climate is a complex topic, and includes researchers studying ecology, geography, economics, etc. Nobody studied them all.

Tetlock. Philip shows how expert opinion is—
☞ The first conclusion one should take from Philip’s work is to disregard it.


{Credibility} Public reason is powered by credibility. Credibility can be applied to claims, to evidence basis, and to authorities.

{Public Reason} Public reason is a race to credibility. We seek credible claims made by credible authorities on the basis of credible evidence. It is not a boxing match.

They’re too useful heuristics to play X-does-not-imply-Y games with Teddie.