Standards of Evidence

A recent post and the resulting kerfluffle (a highly technical term) plus recent comments resulted in me taking some time to reflect on standards of evidence and things of that nature.

Extraordinary claims require extraordinary evidence – Carl Sagan

First, I need to admit to two things.  The first is a bit of personal desire.  You see, I want it to be true that there is life on other planets and perhaps I wasn’t as critical of such claims as I could have been.  I did use a lot of ‘well maybe’ language in the post, but I assumed that the post was legitimate and it looks like it wasn’t.

The second is a bit of journalistic anxiety.  I like writing, but I know I’ll never do a novel (I’ve tried… a lot).  I enjoy teaching, science, technology, etc. and I want to share that.  It wouldn’t hurt my feelings to be asked to be a blogger for a major (or even minor) communication group.  I wanted a scoop.  And I traded my quest for evidence for a chance at being first.  It was wrong.

Now, with those embarrassing lapses out of the way, let’s talk about standards of evidence.

First of all, what is evidence?  Well, that there is a whole ‘nother question.  There doesn’t seem to be a consensus on what evidence is.  As a famous judge says, “I can’t define it, but I know it when I see it.”

To me, scientific evidence is something that is demonstrably true (either a fact or something that can be shown to be a correct statement) that is used to support other statements.

For example, the statement “The grass is my backyard green” is a fact.  A spectrograph of the reflected light of the grass will show that the frequency of light reflected is within the range of what we define as ‘green’.  This fact can be used as evidence for the statement “My lawn is healthy.”  We know that green grass is usually healthy and brown grass is usually unhealthy.  So, my healthy grass statement is supported by evidence.

Now, how do we apply this to science?

Well, let’s say, for example that you have discovered that Einstein’s theory of general relativity was wrong.  Not a little wrong, but completely off the hook.  You write an article that says this.  What kind of evidence do you need?

You need a LOT of evidence.  Einstein’s theory is very, very well supported with mathematical proofs and experimental and observational evidence.  Einstein said that light should bend when passing near massive objects.  This was observationally shown to be true.  Those observations are evidence that Einstein was correct.

If you wanted to overturn Einstein, not only do you have to explain the correct information and explain why Einstein was wrong, but you have to go beyond Einstein, you have to explain why your theory is better.  For example, if your theory did everything Einstein’s general relativity does AND was consistent with quantum mechanics, then you might have something.

At that point, you should be writing papers and have the published in Nature or Science for extensive review by experts in the field.  (One should not attempt to introduce one’s theories to high school level students by legislative action.)  After hundreds of scientists have reviewed your work and many, many experiments have shown you are correct, then you might be placed in textbooks.

Scientists expect this.  They expect hard questions.  Go sit in a six hour thesis defense if you don’t believe me.  Go to a conference and watch the presenter of a paper get hammered for an hour or so.  This is expected, even encouraged.  If no one questions you, then either no one can understand you or your work is insignificant.

Many people, even a few scientists, don’t get this.  They may see the press releases for a new concept and not understand that the six line inches is the result of hundreds (if not thousands) of hours of work.  Days of writing and untold arguments in the cafeteria.

So how does this apply to two major subjects of this blog: aliens and intelligent design?

Aliens: This is a hugely controversial subject.  It will, no doubt, have a huge impact on our society, every culture on the planet, religions and the scientific community and thought.  Further, there have been a fairly consistent stream of claims of this nature from amateur and professional alike for quite a while.  Science is fully aware of the difficulty of not only life outside of our biosphere existing, but it getting to Earth so we can look at it.

There are known to be bacteria very high up in the atmosphere.  That is evidence that many samples of ‘alien’ bacteria that pass through the atmosphere may be contaminated and scientists will have to be prepared to deal with that.  There are a host of other issues and every one will have to be dealt with by the claimant.  That last bit is important.

It is not up to others to support your notions. You have to do the work.  You have to provide the positive claims.

Intelligent Design: The same thing applies here.  There is 150 years of evidence of at least 21 different types that support evolution.  The ID proponent must explain why all of them are wrong.

But that only removes evolution, it does nothing to help Intelligent Design.  There must be positive supporting evidence for ID and there will have to be a lot of it.  After decades of incorrect statements, misrepresentations, and claims that were later proven to be possible without need for the supernatural, ID is pretty much in the same boat that aliens are in.  There needs to be extraordinary evidence to support it.

Again, no one really cares if my lawn is healthy (except for the danged HOA), so my statement and the supporting evidence is trivial.  Something that threatens to overturn 150 years of research is not trivial and the evidence will also have to be non-trivial.

ID especially, but alien claimants too, need to do their own work.  It’s not our job to do their work for them.  It’s also not our job to defend the current scientific consensus.  It’s the scientific consensus for a reason.  The reason is not just because ‘we feel like it’.  It’s so demonstrably correct that no one challenges it anymore.

Sure, people may argue about the relative influence of genetic drift over natural selection, but there is no argument that both influence evolution or the fact that evolution happens and has happened.

Finally, a note about comments.  I’m all for discussion and I’ve had perfectly enjoyable disagreements with people who feel just as strongly one way as I do the other and we remain good friends.  That is the level of discourse that is acceptable here.

If someone asks for evidence, don’t say “There’s tons of evidence.”  Say, “here’s the link to three pieces, if you need more ask me.  Here’s what they say and why they said it that way.”  When you make a claim, back it up.  Give a link or a copy and paste of your own work on the subject.  If someone asks a hard question, they aren’t being stupid or a jerk, they are asking for the benefit of your theory.

If your theory can’t stand up to constant hard questions, then it has no merit.  Ask yourself (and observe others in the comments) if you really answered a hard question with an eye toward making yourself understood, describing why you think the way you do in easy to read, unambiguous language, and is there links to supporting evidence (keeping in mind the extraordinary claim quote above).  If you fluffed off a hard question with a single sentence answer (and part of the answer was “you’re ignorant”), then it’s a clue that your ideas are without evidence (or merit).

Feel free to let me know if this doesn’t make sense or add to it in the comments. What are your definitions of ‘evidence’?

With that, my son wants to go play football.  See ya.