The meaning of evidence

[Sherlock Holmes]

This thread is to discuss the meaning of the term "evidence" particularly with respect to claims made by evolution advocates.

The reason I started this thread is that I often see - what I regard as - a conflation of consistent with and evidence for. If we are to make reasonable inferences and maintain objectivity and avoid making assumption unwittingly then the more precisely we define "evidence" the better I think.

The biggest risk here is to imply that some observation P is evidence for X and only X, rather than evidence for X and Y or Z. Unless we are on our guard we can informally exclude reasonable possibilities Y and Z and so on. Now the observation P might well be evidence for X and only X, but unless that is soundly established we simply can't assume that.

If we mistakenly regard P as evidence for X and only X then we fall into the trap of believing that P can only be observed if X was the cause.

This is exemplified by an analogy I recently put together that I think warrants its own thread, so here it is:

Consider this jigsaw

None of the circles overlap, we can see this when we can see the totality of the jigsaw. But if we already believed for some reason or other, that they must overlap and we only had twenty random pieces and never see the rest, we could make up a jigsaw (theory) where we "fill in the blanks" so to speak and "show" that we sometimes have overlapping circles.

We'd be absolutely right too in saying the twenty pieces were consistent with an image that has overlapping circles, but we'd be dead wrong to say the twenty pieces are evidence of overlapping circles, because as we know, none of the circles actually do overlap.

So do you agree or not, there's a difference between observations that are evidence for some hypothesis vs consistent with some hypothesis and we should always be careful and make this distinction clear in our arguments?

[Difflugia]

Now I just gotta...

One of my favorite albums of all time, but for some reason I haven't listened to it in years. I'm fixing that now.

[Sherlock Holmes]

[Replying to Sherlock Holmes in post #123]

To suggest that biological molecular systems of enormous complexity can achieve this kind of robustness and be free from long term degradation, without any design teams is just one reason that some of us are extremely skeptical of the grandiose claims made by some evolutionists, James Tour is but one example.

I've also written many hundreds of programs since my first Fortran punched card version in 1976, some very involved with thousands of lines of mainly number crunching code, and the goal of those efforts was indeed robustness and reliability. But evolution (as Barbarian alluded to) is so powerful for the very reason that is isn't "perfect" and working towards some goal. The flexibility in its mechanisms is what allows adaptation and speciation to occur so that living things can continue to adapt and change under natural selection.

So it seems strange that you would doubt biological molecular systems of enormous complexity can arise via evolution, when its mechanisms allow exactly that kind of thing to happen.

Well basically I'm alluding to the fact that evolutionists ignore unintended consequences when they extrapolate. Form observations made showing small changes over short time frames, they extrapolate that larger and larger deviations from some start genome over longer and longer time is undoubtedly feasible. But how can that be claimed when there might well be self limiting mechanisms or constraining mechanisms that are simply not evident in a lab, might only begin emerge after thousands or hundreds of thousands of years?

That the process has adaptive abilities is not questioned, I've seen the data and experiments on bacteria to recognize that, but while adaptation is obviously necessary it simply might not be sufficient. Adaptation might do nothing more than preserve some colony in the face of environmental changes, it might lead to nothing more than overall survival without new novel features. I mean look at the history, the earth is 4.5 BY old, life appeared around 3.5 BY ago and the first eukaryotes appeared 1.8 BY ago. So for some 1.7 BY (1,700,000,000 years!) nothing much happened, no novelties, just presumably adaptation - survival.

The bottom line is one can argue all day about this but what I say is reasonable and relevant we cannot show that the process does not suffer from long term unintended consequences that serve to constrain genome change. The genome changes we infer from the record do not prove that evolutionary processes was their source.

The software analogy is just an attempt to put this in perspective, how humans - who understand computing machines perfectly - are unable to reliably create non trivial systems without unforeseen problems emerging. We - humans - are confident we understand what an FSM is, what a CPU does and so on, yet despite knowing EVERYTHING about that (down to instruction timings and so on, you understand me here) the systems we create are hard to test, always contains bugs and unforeseen pitfalls that can only be found by actually running the software, no amount of static code analysis can reveal some of the problems as I'm sure you - an engineer - can appreciate yourself.

To claim that even more complex and delicate systems absolutely cannot fall victim to similar problems strikes me as wishful thinking.

Now by all means disagree, but I have to ask, am I being stupid here? am I being unreasonable? I think this is a perfectly reasonable objection, I don't think espousing such a view should elicit laughter and dismissal as is often the case when an attempt is made to seriously scrutinize the arguments that underpin the belief in evolution.

[Sherlock Holmes]

[Replying to JoeyKnothead in post #129]

A few years ago my pretty thing and I had a pair of Love Birds. They produced three lovely little Love Birds, well eggs that hatched into little Love Birds. After watching shows on the TV where birds pushed their little ones off cliffs and such to teach them how to fly, I wondered how we'd teach our little brood to fly. One day while holding them in my lap, they simply took off and flew up to land on one of our curtain rods. I suspect pigs learn to fly just as easily. Of course, most curtain rods wouldn't hold them.


Tcg

I have to admit there is a grain of truth to this, in fact some early steps have been taken to acclimatize pigs with at least moving rapidly through the air and they seem to take to it well.

[Sherlock Holmes]

Now I just gotta...

One of my favorite albums of all time, but for some reason I haven't listened to it in years. I'm fixing that now.

I listened to early Floyd in my teens and early twenties, the tragic decline of Syd Barret is a huge loss to the music world, this is one of the most imaginative tracks he ever composed - IMHO - the musicality is astonishing:

Huge memories of a care free 1960s as I grew up in Liverpool, Beatles and so on, The Prisoner TV series, The Avengers, Dr Who, totally different world.

[Jose Fly]

Well basically I'm alluding to the fact that evolutionists ignore unintended consequences when they extrapolate.

Are you referring to anything specific, or is this an appeal to your own imagination?

Form observations made showing small changes over short time frames, they extrapolate that larger and larger deviations from some start genome over longer and longer time is undoubtedly feasible. But how can that be claimed when there might well be self limiting mechanisms or constraining mechanisms that are simply not evident in a lab, might only begin emerge after thousands or hundreds of thousands of years?

If you have evidence of the existence of these alleged mechanisms, present it. Otherwise you're merely invoking unspecified things that only exist in your imagination and wondering why scientists don't take them into account. Hopefully you think about it a bit and eventually understand why that is.

The bottom line is one can argue all day about this but what I say is reasonable and relevant we cannot show that the process does not suffer from long term unintended consequences that serve to constrain genome change.

Again, so far these "unintended consequences" only exist in your imagination.

The genome changes we infer from the record do not prove that evolutionary processes was their source.

Why not?

Now by all means disagree, but I have to ask, am I being stupid here? am I being unreasonable?

You're invoking imaginary and unspecified mechanisms and wondering why scientists haven't taken them into account. The obvious response is, if you can't say what they are or show that they even exist, how can anyone take them into account?

From my POV, it doesn't seem like you've really thought this through.

[Sherlock Holmes]

Well basically I'm alluding to the fact that evolutionists ignore unintended consequences when they extrapolate.

Are you referring to anything specific, or is this an appeal to your own imagination?

Form observations made showing small changes over short time frames, they extrapolate that larger and larger deviations from some start genome over longer and longer time is undoubtedly feasible. But how can that be claimed when there might well be self limiting mechanisms or constraining mechanisms that are simply not evident in a lab, might only begin emerge after thousands or hundreds of thousands of years?

If you have evidence of the existence of these alleged mechanisms, present it. Otherwise you're merely invoking unspecified things that only exist in your imagination and wondering why scientists don't take them into account. Hopefully you think about it a bit and eventually understand why that is.

The bottom line is one can argue all day about this but what I say is reasonable and relevant we cannot show that the process does not suffer from long term unintended consequences that serve to constrain genome change.

Again, so far these "unintended consequences" only exist in your imagination.

The genome changes we infer from the record do not prove that evolutionary processes was their source.

Why not?

Now by all means disagree, but I have to ask, am I being stupid here? am I being unreasonable?

You're invoking imaginary and unspecified mechanisms and wondering why scientists haven't taken them into account. The obvious response is, if you can't say what they are or show that they even exist, how can anyone take them into account?

From my POV, it doesn't seem like you've really thought this through.

Jose, with all due respect, I didn't "invoke" anything. I pointed out some facts about man made mechanisms (computer running software) and how these routinely reveal the presence of unintended consequences, detrimental emergent behaviors (aka "bugs") that often only appear over the longer term.

I then asked how can we be confident about evolution taking place over millions of years based on real world tests that span only a few years, we can test software for a week or two, sign it off and deploy it only to find examples starting to misbehave after a year in the field (Oh man, we forgot that the 32 bit counter would wrap around or Oh man we never expected a division by zero at that point, I mean we check for that at step 127, how on earth could that...).

In other words biological systems too, might also contain "bugs" that are only observable after a 100,000 years, in which case we'd never know of them would we? These in turn might be bugs that inhibit the kind of evolution you are so confident took place.

Basically complex state based systems (of which DNA + cell machinery is an example) cannot be claimed defect free after testing for only short periods. If we extrapolated software "its ran fine for 24 hours therefore will run fine for 24 years" the way evolution advocates extrapolate "we've seen evolution in the lab take places over several months of testing therefore we expect this to continue for ten million years" we'd be wrong, certainly complex state based man made systems cannot have their behavior extrapolated reliably for anything but the most trivial cases.

[Jose Fly]

I pointed out some facts about man made mechanisms (computer running software) and how these routinely reveal the presence of unintended consequences, detrimental emergent behaviors (aka "bugs") that often only appear over the longer term.

FYI, populations of organisms are not man-made computer software.

I then asked how can we be confident about evolution taking place over millions of years based on real world tests that span only a few years, we can test software for a week or two, sign it off and deploy it only to find examples starting to misbehave after a year in the field

This is the fallacy of false analogy.

In other words biological systems too, might also contain "bugs" that are only observable after a 100,000 years, in which case we'd never know of them would we? These in turn might be bugs that inhibit the kind of evolution you are so confident took place.

Like what?

Basically complex state based systems (of which DNA + cell machinery is an example) cannot be claimed defect free after testing for only short periods.

What do you mean by "defect free"? What specific defects are you referring to?

If we extrapolated software "its ran fine for 24 hours therefore will run fine for 24 years" the way evolution advocates extrapolate "we've seen evolution in the lab take places over several months of testing therefore we expect this to continue for ten million years" we'd be wrong, certainly complex state based man made systems cannot have their behavior extrapolated reliably for anything but the most trivial cases.

Do you hold the same view with tectonics, glacial erosion, galaxy formation, planetary orbits, and all other long-term processes?

[Sherlock Holmes]

I pointed out some facts about man made mechanisms (computer running software) and how these routinely reveal the presence of unintended consequences, detrimental emergent behaviors (aka "bugs") that often only appear over the longer term.

FYI, populations of organisms are not man-made computer software.

I then asked how can we be confident about evolution taking place over millions of years based on real world tests that span only a few years, we can test software for a week or two, sign it off and deploy it only to find examples starting to misbehave after a year in the field

This is the fallacy of false analogy.

In other words biological systems too, might also contain "bugs" that are only observable after a 100,000 years, in which case we'd never know of them would we? These in turn might be bugs that inhibit the kind of evolution you are so confident took place.

Like what?

Basically complex state based systems (of which DNA + cell machinery is an example) cannot be claimed defect free after testing for only short periods.

What do you mean by "defect free"? What specific defects are you referring to?

If we extrapolated software "its ran fine for 24 hours therefore will run fine for 24 years" the way evolution advocates extrapolate "we've seen evolution in the lab take places over several months of testing therefore we expect this to continue for ten million years" we'd be wrong, certainly complex state based man made systems cannot have their behavior extrapolated reliably for anything but the most trivial cases.

Do you hold the same view with tectonics, glacial erosion, galaxy formation, planetary orbits, and all other long-term processes?

I stated my case, my opinion and that's that. Tell me how can you prove that behavior of a complex state based system (i.e. a colony of bacteria) observed over a period of a few years will not exhibit additional unanticipated emergent behavior over a period of say a few thousand years?

Also note, you say "populations of organisms are not man-made computer software" then tell that to evolution researchers Jose, researchers who want to simulate evolution using software! Tell them they are seeking a "false analogy"!

I can well imagine what you'd say if they simulated complex evolution with software and I screamed "Nah, that's a false analogy".

[Jose Fly]

I stated my case, my opinion and that's that.

And I see that case as fallacious, uninformed, and very weak (at best).

Tell me how can you prove that behavior of a complex state based system (i.e. a colony of bacteria) observed over a period of a few years will not exhibit additional unanticipated emergent behavior over a period of say a few thousand years?

Fallacy of shifting the burden of proof. If you have evidence for the existence of such behavior, then present it. If you can't, then there's nothing to discuss and nothing for evolutionary biologists to consider.

[Sherlock Holmes]

I stated my case, my opinion and that's that.

And I see that case as fallacious, uninformed, and very weak (at best).

Tell me how can you prove that behavior of a complex state based system (i.e. a colony of bacteria) observed over a period of a few years will not exhibit additional unanticipated emergent behavior over a period of say a few thousand years?

Fallacy of shifting the burden of proof. If you have evidence for the existence of such behavior, then present it. If you can't, then there's nothing to discuss and nothing for evolutionary biologists to consider.

Jose for the third time I never said there was or would be such behavior, I asked how can we justify the assumption that there won't be unintended consequences, it is an assumption and it needs to be called out as an assumption not swept under the rug and referred to as a "fact".