All tautologies are truisms, but not all truisms are tautologies. - Edit 1
Before modification by Joel at 06/08/2011 09:40:45 PM
A truism is a statement of obvious fact; a tautology deceptively "compares" a thing to itself to "prove" an unsubstantiated proposition. One is just a formal declaration of something self evident; the other is disingenuous bootstrap levitation.
I think I understood the TO/IN in the way you explain it and your explanation sort of agrees with what LadyLorriane tried to say.
The tautology problem does not go away with your way of explaining it though, since you don't tell us how we "know" what individuals will be selected, before they are selected. Yes, taking in mind that we are dealing with probability, rather than with absolute numbers.
If a new individual is born, even when given all the possible information about it's DNA and it's environment, (and given that this individual does not have an obvious and gigantic disability), how would you determine it's "benefit in the environment" or it's "chances to procreate" before it actually happens? My point is that you can only measure that afterwards and if it can only be measured afterwards, it cannot be predicted or tested.
It can be tested, just not predicted; however, I'd wager most people would say the goal is a description rather than a prediction of the process. That is to say, not to identify which traits are most helpful to their possessors and document their growing prevalence as evidence of natural selection, but to document helpful traits enhancing survival and thereby predominating in future generations as evidence of natural selection. I think what we're dealing with is a truism rather than a tautology, and while the two are very similar, there are critical differences: A truism is a statement of undeniable fact, like "2+2=4"; a tautology is an equivalency masquerading as a comparison, like "2+2 resembles 4".
For this part I would like to refer to my latest responce to Belals Girl.
I'm not sure you understand the problem I have with a tautology (or a truism for that matter). If NS is a tautology, OR a truism doesn't matter for my argument. It is true. No problem. Of cource it is true and in fact, when stated in tautological or truistic form, I totally agree with NS.
The problem is that it does not explain anything, other than that it describes a pattern we observe in nature in a way that makes sense.
I don't think the concept of natural selection aspires to more than sensibly describing a pattern observed in nature. It defines a process, not a specific outcome.
Technically I could argue that this is on the edge of a discription of the proces of NS and the result of NS.
Maybe it's better to limit NS to the fact that some organisms survive and others don't and that a pattern of frequency can in some way be related (if only potential) to specific (genetic) traits. This causes a shift in the frequency of genes in the gene pool.
The fact we observe shifts in frequencies proves that nature has been selecting (given the fact that the science of statistics needs sufficient data to make such claims).
But when we say that NS = change (of the frequencies of genes) in the gene pool, while we can only determine NS by observing this change, then we have a tautology (or truism if you prefer). An observation. In fact, an observation that can not be "tested" since you can not predict how (or even that) the gene pool wil change.
Because it changes most of the time (if only a little) in most species we can "predict" that it wil change in any given species over several generations, but we already knew that.
And even if it does not change, we could postulate that there have been new traits, but that NS has prevented them from entering the gene pool.
Hence, NS cannot be falsified, since any observation can be explained by NS.
No, only observations consistent with natural selection can be explained by it; observations inconsistent with it cannot, and that's the test: If we observe the former natural selection is supported, if we observe the latter, it is not. Very falsifiable. Yes, natural selection equals a change in the frequency of a beneficial gene within a populace, thus observing that change is evidence of natural selection. That's a truism, but NOT a tautology. "Survival of the fittest" is a tautology because it pretends that the former is distinct from and the effect of the latter, and for that reason diguises the fact the phrase treats the terms as synonymous.
I've checked Wikipedia, but as far as I can tell this is still a tautology (notice your phrase "by definition"
, but it doesn't matter concerning my point.
It matters a great deal, because you seem to be dismissing anything and everything substantiating a proposition, on the grounds such evidence makes it a tautology.
Here you speak of "all evidence supports it", my whole point is that of cource all evidence supports it, since there is no way I can think of a test that would produce evidence that does not support it. Even when given a universe where all laws of nature are different and life being made of gold atoms and electrons in a shell of uranium, there is simply no way any test can ever produce evidence to the contrary. That's the problem.
The test you described in your response to BG is just such a test, because in case A and B we would see that organisms possessing a trait undeniably enhancing their own survivability nonetheless did NOT become more prevalent in the gene pool over time. Explaining that would be quite a challenge, but fortunately I'm not aware of anything that might present it.
A benefit TO the environment seems like going too far, because that statement itself is an entry into the philosophical, but an increased survival rate is a metric for benefits IN the environment: The greater survival of organisms with a certain trait in a certain environment over that of organisms without it suggests a natural, mechanical and non-directed selection for such traits generally. Without guidance, traits that help an organism in a given environment come to predominate over those that either don't help or even harm organisms, because organisms with helpful traits live longer and breed more than others. The scientific test of the theory is whether we can observe the results it predicts over time: If we do, that's evidence the theory is valid; if not, that's counterevidence (bearing in mind, as always, that evidence does not necessarily reach the level of conclusive proof).
That's just one laymans limited understanding though, so take it for what it's worth; there's a reason I didn't leap up to give my opinion.
That's just one laymans limited understanding though, so take it for what it's worth; there's a reason I didn't leap up to give my opinion.
I think I understood the TO/IN in the way you explain it and your explanation sort of agrees with what LadyLorriane tried to say.
The tautology problem does not go away with your way of explaining it though, since you don't tell us how we "know" what individuals will be selected, before they are selected. Yes, taking in mind that we are dealing with probability, rather than with absolute numbers.
If a new individual is born, even when given all the possible information about it's DNA and it's environment, (and given that this individual does not have an obvious and gigantic disability), how would you determine it's "benefit in the environment" or it's "chances to procreate" before it actually happens? My point is that you can only measure that afterwards and if it can only be measured afterwards, it cannot be predicted or tested.
It can be tested, just not predicted; however, I'd wager most people would say the goal is a description rather than a prediction of the process. That is to say, not to identify which traits are most helpful to their possessors and document their growing prevalence as evidence of natural selection, but to document helpful traits enhancing survival and thereby predominating in future generations as evidence of natural selection. I think what we're dealing with is a truism rather than a tautology, and while the two are very similar, there are critical differences: A truism is a statement of undeniable fact, like "2+2=4"; a tautology is an equivalency masquerading as a comparison, like "2+2 resembles 4".
For this part I would like to refer to my latest responce to Belals Girl.
I'm not sure you understand the problem I have with a tautology (or a truism for that matter). If NS is a tautology, OR a truism doesn't matter for my argument. It is true. No problem. Of cource it is true and in fact, when stated in tautological or truistic form, I totally agree with NS.
The problem is that it does not explain anything, other than that it describes a pattern we observe in nature in a way that makes sense.
I don't think the concept of natural selection aspires to more than sensibly describing a pattern observed in nature. It defines a process, not a specific outcome.
Natural selection, as I understand it, is the phenomenon of traits enhancing survival predominating over time as they become an increasingly large part of the gene pool, forcing out less useful traits.
Technically I could argue that this is on the edge of a discription of the proces of NS and the result of NS.
Maybe it's better to limit NS to the fact that some organisms survive and others don't and that a pattern of frequency can in some way be related (if only potential) to specific (genetic) traits. This causes a shift in the frequency of genes in the gene pool.
The fact we observe shifts in frequencies proves that nature has been selecting (given the fact that the science of statistics needs sufficient data to make such claims).
But when we say that NS = change (of the frequencies of genes) in the gene pool, while we can only determine NS by observing this change, then we have a tautology (or truism if you prefer). An observation. In fact, an observation that can not be "tested" since you can not predict how (or even that) the gene pool wil change.
Because it changes most of the time (if only a little) in most species we can "predict" that it wil change in any given species over several generations, but we already knew that.
And even if it does not change, we could postulate that there have been new traits, but that NS has prevented them from entering the gene pool.
Hence, NS cannot be falsified, since any observation can be explained by NS.
No, only observations consistent with natural selection can be explained by it; observations inconsistent with it cannot, and that's the test: If we observe the former natural selection is supported, if we observe the latter, it is not. Very falsifiable. Yes, natural selection equals a change in the frequency of a beneficial gene within a populace, thus observing that change is evidence of natural selection. That's a truism, but NOT a tautology. "Survival of the fittest" is a tautology because it pretends that the former is distinct from and the effect of the latter, and for that reason diguises the fact the phrase treats the terms as synonymous.
Organisms with traits enhancing survival are, by definition, more likely to survive and pass on those traits, and those without them are less likely; that's a truism, not a tautology.
I've checked Wikipedia, but as far as I can tell this is still a tautology (notice your phrase "by definition"
, but it doesn't matter concerning my point.It matters a great deal, because you seem to be dismissing anything and everything substantiating a proposition, on the grounds such evidence makes it a tautology.
Identifying such traits specifically is immaterial to verifying the occurrence of that process; in fact, the attempt can actually prejudice it because traits that might initially seem more beneficial can prove otherwise in practice. It's difficult to dispute the occurrence of natural selection as defined above, because it's what we would logically expect and all evidence supports it (again, it's important to note that's not automatically proof, just very compelling evidence). An independent opposing force would almost be required to PREVENT it.
Here you speak of "all evidence supports it", my whole point is that of cource all evidence supports it, since there is no way I can think of a test that would produce evidence that does not support it. Even when given a universe where all laws of nature are different and life being made of gold atoms and electrons in a shell of uranium, there is simply no way any test can ever produce evidence to the contrary. That's the problem.
The test you described in your response to BG is just such a test, because in case A and B we would see that organisms possessing a trait undeniably enhancing their own survivability nonetheless did NOT become more prevalent in the gene pool over time. Explaining that would be quite a challenge, but fortunately I'm not aware of anything that might present it.