Since the Theory of Evolution is in the business of explaining the past and present rather than predicting the future, it certainly runs the risk of deluding itself. But running a risk is not the same thing as failing. And whenever individual biologists succumb to hindsight bias, there are other biologists ready to point out their mistakes.
Evolutionary biology is a remarkably introspective discipline with plenty of remora-like philosopher-commensals waiting to devour any sloppy thinking that gets generated. See, for example, the wikipedia article on “The Spandrels of Sam Marco” or on G. C. Williams’s book “Adaptation and Natural Selection”. Or, check the high level of scorn in which practitioners of unfalsifiable “Evolutionary Psychology” are held by other evolutionary scientists.
Evolutionary biology is (in part) a historical science in which hypotheses about the past are used to explain features of the present. So too is geology and much of astro-physics. This class of scientific disciplines certainly seems to run afoul of the deprecation which Eliezer dispenses in the final paragraph of his posting. But, no problem. Other philosophers are on the case, and they point out that this way of doing science can still be ok, in spite of the natural human tendency toward hindsight-bias, so long as you are careful to check that you get more bits worth of explanation out than you feed bits of hypothesis in. The evolutionary meta-hypothesis of common descent and the various more detailed hypotheses (such as that man diverged from chimp roughly 6 million years ago in Africa) have definitely yielded far more information in explanation that was supplied in hypothesis.
But there are many aspects of evolutionary biology that can be tested using methods of which Eliezer’s final paragraph would approve. For example the theories of evolutionary mechanism (random mutation, natural selection, and drift) can and have been tested in the lab and in the field. And, most importantly, we can reasonably extrapolate these observations of small-scale evolution in a short time to hypotheses of large scale evolution over deep time. What justifies this extrapolation? Well, one thing that does is the modern validation of Darwin’s prediction that, once the underlying basis of heritable variation were known, it would be confirmed that variation between species is the same kind of thing as variation within species—only more so. And as anyone who knows some molecular genetics can testify, Darwin’s prediction has been spectacularly confirmed in the genomics era.
“Since the Theory of Evolution is in the business of explaining the past and present rather than predicting the future”
Ouch! I hope not! That makes it sound awful! Theories should be consistent with existing observations—sure—but a bigger challenge for them comes in predicting new observations before they are made.
I think the key is that theories don’t predict the future at all.
They predict observations.
Because of my model, I expect to see X under the given conditions. If I test for X, and I do not find it, this is evidence that my model is wrong. If I test for X and find it, this is evidence that my model is correct.
This says nothing about the future or past, only what you have and have not observed yet, and what you expect to observe next (which can be about the future or past, it doesn’t matter).
There is at least one rather specialised area in which theory offers predictions—evolution of communities. It’s like, ‘when true grasses appeared, they made, through having some novel features, created grasslands. They circumvented successions that would lead to preexistent plant habitats; in the beginning, they were weeds compared to the rest of vegetation. Nowadays, we have a group of species that spread widely, are considered weeds and share ecological similarity, not [relatively recent] common ancestor. We predict that in future, these weeds will form habitats through disruption of current eco networks.’ Admittedly, this is hard to observe.
Since the Theory of Evolution is in the business of explaining the past and present rather than predicting the future, it certainly runs the risk of deluding itself. But running a risk is not the same thing as failing. And whenever individual biologists succumb to hindsight bias, there are other biologists ready to point out their mistakes.
Evolutionary biology is a remarkably introspective discipline with plenty of remora-like philosopher-commensals waiting to devour any sloppy thinking that gets generated. See, for example, the wikipedia article on “The Spandrels of Sam Marco” or on G. C. Williams’s book “Adaptation and Natural Selection”. Or, check the high level of scorn in which practitioners of unfalsifiable “Evolutionary Psychology” are held by other evolutionary scientists.
Evolutionary biology is (in part) a historical science in which hypotheses about the past are used to explain features of the present. So too is geology and much of astro-physics. This class of scientific disciplines certainly seems to run afoul of the deprecation which Eliezer dispenses in the final paragraph of his posting. But, no problem. Other philosophers are on the case, and they point out that this way of doing science can still be ok, in spite of the natural human tendency toward hindsight-bias, so long as you are careful to check that you get more bits worth of explanation out than you feed bits of hypothesis in. The evolutionary meta-hypothesis of common descent and the various more detailed hypotheses (such as that man diverged from chimp roughly 6 million years ago in Africa) have definitely yielded far more information in explanation that was supplied in hypothesis.
But there are many aspects of evolutionary biology that can be tested using methods of which Eliezer’s final paragraph would approve. For example the theories of evolutionary mechanism (random mutation, natural selection, and drift) can and have been tested in the lab and in the field. And, most importantly, we can reasonably extrapolate these observations of small-scale evolution in a short time to hypotheses of large scale evolution over deep time. What justifies this extrapolation? Well, one thing that does is the modern validation of Darwin’s prediction that, once the underlying basis of heritable variation were known, it would be confirmed that variation between species is the same kind of thing as variation within species—only more so. And as anyone who knows some molecular genetics can testify, Darwin’s prediction has been spectacularly confirmed in the genomics era.
“Since the Theory of Evolution is in the business of explaining the past and present rather than predicting the future”
Ouch! I hope not! That makes it sound awful! Theories should be consistent with existing observations—sure—but a bigger challenge for them comes in predicting new observations before they are made.
I think the key is that theories don’t predict the future at all.
They predict observations.
Because of my model, I expect to see X under the given conditions. If I test for X, and I do not find it, this is evidence that my model is wrong. If I test for X and find it, this is evidence that my model is correct.
This says nothing about the future or past, only what you have and have not observed yet, and what you expect to observe next (which can be about the future or past, it doesn’t matter).
There is at least one rather specialised area in which theory offers predictions—evolution of communities. It’s like, ‘when true grasses appeared, they made, through having some novel features, created grasslands. They circumvented successions that would lead to preexistent plant habitats; in the beginning, they were weeds compared to the rest of vegetation. Nowadays, we have a group of species that spread widely, are considered weeds and share ecological similarity, not [relatively recent] common ancestor. We predict that in future, these weeds will form habitats through disruption of current eco networks.’ Admittedly, this is hard to observe.