Scientific Consensus is Not Just a Raised Hand!

In a recent conversation, the subject of scientific consensus was raised and their reaction was fascinating.  They immediately dismissed it as something that does more damage than good.  What it told me is they have absolutely no idea how scientific consensus is achieved and what it takes to change that consensus.

Here's my issue in a nutshell, remember the conversation about the words 'theory' and 'belief'?  In the colloquial sense they mean one thing, but when you look at the scientific sense, they mean something very different.  That's what's going on here.  'Consensus' and 'Scientific Consensus' are incredibly different.

To them, consensus is nothing more than a group agreeing on something, as if a bunch of scientists sat in a room and the majority raised their hand when a topic was announced.    Suppose someone on the radio says something, and a group of people call in and most agree with it.  A good example of Rush Limbaugh's 'Ditto-Heads', which are people who call in but instead of re-hashing and taking up airtime, they just say 'Ditto!' to show their agreement.  You can say that the group that called in has consensus if the majority who called in agree with the statement.

But, does that mean the consensus is right or wrong?  Or even closer to right or closer to wrong if you don't want to address absolutes?  With the idea of the colloquial term 'consensus', there is no way to make a value statement.  The only thing you know is that the call-in group agreed.  That's not a scientific consensus.  Like other words often misused by pseudo-scientists, that's horrible example of a scientific consensus.  The idea of a scientific consensus is something much more, considerably more.

Here's the Wikipedia explanation:

"Scientific consensus is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity.
Consensus is normally achieved through communication at conferences, the publication process, replication (reproducible results by others), and peer review. " (Wikipedia: Scientific Consensus)

A few things to note:

• A community of scientists in a particular field of study -- in other words the only ones who count are the ones who are in a particular field.  These are the people who study a subject and the agreement of people outside the field is simply opinion.
• General agreement  . . . not unanimity -- which, of course means, that the entire group doesn't have to be agreement, but the clear majority of the scientists working in a specific field agree, but not by a vote, through a number of other mechanisms, including:
• Conferences -- We aren't talking about a matter of opinion, scientists present to their peers and if you have ever presented to a group of co-workers, you know this isn't just a 'because I said so' presentation.  They present not just their conclusions, but details about exactly how they came to those conclusions -- and then the fun begins.  Their conclusion are not just examined, but their entire methodology.  Scientists do not go into these conferences voicing a simply opinion.
• Publications -- Similar to conferences, publications are another avenue for communication.  One difference, publications usually go into a great deal more detail than a conference can.  The level of detail has to be enough for other scientists to fully understand and even replicate the work.
• Replication -- Here is an important piece, scientific conclusions that cannot be replicated never reach a level of consensus.  The details from those conferences and publications are replicated, not by the originating scientist, but others in the same field, often competitors.  If it cannot be replicated, it eventually falls to the wayside (ask the Cold Fusion guys).
• Peer review --  Here one of the biggest differences between the colloquial 'consensus' and the scientific consensus.  Before publication, scientific papers are reviewed at the request of the publication editor.  It is sent to the author's competitors, again members of the same field, for review.  Most often this is a blind review, the author doesn't know who is reviewing it, and the reviewers don't know who the author is.  These reviewers don't just give a thumbs-up or down, but document issues they had with the paper.  The editor typically has multiple options, commonly:
• Outright rejection -- which is usually done when the paper doesn't meet publishing standards.  It could be the subject is outside the publications purview or it may have massive technical or procedural errors.
• Editing the paper -- Normally when the reviewers find minor errors that can be fixed without changing the meaning of the paper.  Many scientists aren't professional technical writers, so often there are editorial changes to clean things up, so to speak.
• Return the paper to the author -- which is usually done to give the author the chance to address those concerns and re-submit at a later time.

You see Scientific Consensus is not just a bunch of scientists all nodding their head, but a concerted effort to make sure that there is a general agreement on a specific subject through a number of mechanisms that cause the concept to be evaluated.  Not an absolute agreement, but a general one based on such evaluations.  Scientists are free to disagree with minor or major parts as they see fit, and often that is where future scientific work is directed.  But rarely do scientists go against consensus without some evidence that there is a reason for doing so, evidence is the key.

Opponents like to build a very rosy picture of the scientific community, how they all work together, all for some altruistic goal.  The reality is much different.  There is a surprising amount of conflict, both professional and personal.  In fact many of the most lauded scientific achievements are done by scientists who buck the consensus.  But the key is they buck it with evidence, not wishful thinking.

Is scientific consensus a perfect thing?  No, but can anyone name a better process?  The Discovery Institute has tried a couple.  For example, they keep trying to sell the idea that opinion is just as valuable at scientific consensus.  They also like to publish articles and books without a single critical review from anyone outside their own group of believers.  People like Answers in Genesis keep trying to tell you how wrong science is on certain things without a lick of evidence to support their contention.

But when it comes to explanations that actually match the evidence and are usable and workable, scientific consensus seems to work really well.  If someone has a better idea, let's hear it.  But until there is one, scientific consensus is one of our best methods for understanding the world around us.