The
 CAGW debate has sometimes been an emotionally charged exchange of views
 between warmists and skeptics that has often been punctuated with the 
use of logically invalid arguments. Ad hominems are a regular occurrence
 as are attempts to misdirect attention away from the claims being made 
to the character of the claimer(s). 
Sometimes
 a speaker’s credentials are impugned in an attempt to shut them up or 
to convince others not to put much import in what they say because they 
are not qualified
 to speak on the matter. It is used to misdirect attention from the 
claim under discussion to the education of the speaker. It is a 
variation on the ‘who said’ argument. 
Was
 it Aquinas who advised: Ask not who made the claim ask if the claim is 
true. If it  were possible to resurrect him and bring Aquinas forward 
into our age it is probable that he would like to add two corollaries to
 his epithet. Ask not how many made the claim ask if the claim is true. 
And finally, ask not who funded the claim ask if the claim is true. The 
who, how many and who funded subjects are red herrings designed to draw 
your attention away from whether the claim is true. To employ these 
arguments as valid on a logic exam would attract a failing grade.
Who would use such invalid arguments? Why would they need them?
This
 argument is particularly irksome to me as it implies that only experts 
can have a correct opinion on the matter in question. Is it used because
 the objector is feeling insecure about his ability to defend his 
position? 
The
 argument against the ‘argument from credentials’ is to point out that 
not everyone is a chicken and may not know how to lay an egg but as long
 as one’s nose is in working order anyone can tell when one is rotten.
Just because a person does not possess a Phd degree does not disqualify her remarks as being without merit. Take the example of the African teenager
 whose observation solved two problems at once. The solution had not 
occurred to any Phds who have studied lions. The teen’s invention saves 
the lions from being hunted and shot and it protected his family’s 
livestock upon which they depend for their living. Your education does 
not matter. It is your thoughts that matter and they must be taken at 
their face value and not pre-judged based on who utters them. His 
invention allows lions and humans to live together in harmony. What 
could be better than that? No Phd required. 
Freedom
 of speech is not reserved to experts. It is available to all and all 
comments on a topic are to be valued even if they turn out to be wrong. 
People who go down dark alleys and find a dead end provide a useful 
service to the rest of us. We don’t have to make the same mistake so our
 time and efforts can be better directed elsewhere. Mistakes confer 
knowledge that is useful to the tribe at large. 
Neither
 your education nor your years of experience in the field necessarily 
qualify your opinions as inviolate. Anyone, including a Kenyan teenager,
 can add to the sum total of human knowledge. 
That
 is one reason that freedom of speech is so valuable a human right. The 
greater our population the larger the number of minds we have working on
 our problems. Solutions can come from anywhere including the ‘Lion 
Lights’ of an astute Kenyan, Richard Turere, 13.
Let
 us keep the focus on the evidence. Let us hear and see what Mother 
Nature is doing. After all, it is only her credentials that count.