One line of “evidence” involved WEiT’s descriptions of causal condations that presumably resulted in changes between major morphological forms.
As concluded in that post, WEiT’s explanations were based on terms that represent speculation rather than observations obtained by experimental testing (as specified by WEiT and Fitzhugh below), and thus, by the book’s own science criteria, do not suffice as plausible test evidence.
Thus this line of "evidence" can be ruled out as providing support that Darwinism’s tenets have been verified.
The second line of evidence involved examples of “fulfilled predictions” that, in one way or another, were based on the prediction of the discovery of new organisms whose morphological traits would be sufficiently similar to the previously documented assumed transitional-form sequences (in both extinct and extant organisms) to be interpreted as a trait (organism) in the originally documented sequence.
WEiT states that there are two "kinds" of evidence that verifies Darwinism, the first specified in the following:
So how do we test evolutionary theory — . There are actually two kinds of evidence. The first comes from using the six tenets of Darwinism to make testable predictions. By predictions, I don’t mean that Darwinism can predict how things will evolve in the future. Rather, it predicts what we should find in living or ancient species when we study them. Here are some evolutionary predictions. (page 17) [emphasis supplied]
Following this perception of testing evolutionary theory with predictions, WEiT lists the first "kind" of predictions (that should be associated with the book’s six Darwinism tenets) summarized as follows by their principle concepts (pages 18 & 19).
— change in the fossil record;
— species dividing into two or more;
— species that link together major groups as suspected common ancestry;
— species that show genetic variation for many traits;
— cases of imperfect adaptation;
— see natural selection acting in the wild.
The goal for this post is to examine the plausibility of "evidence," presented by WEiT as “fulfilled predictions,” that were derived according to the following analytical sequence, which describe the general procedure utilized in the book’s prediction examples.
1. A series of known fossil organisms or organism traits are presented as a sequence of diversification of morphological forms.
2. It is predicted that additional fossil organisms will be discovered that exhibit enough morphological similarities between two forms in the known sequence to be judged as intermediate organisms in the sequence.
3. Such an organism is discovered.
4. Thus, the prediction is fulfilled, with some sort of implied application to Darwinism’s verification.
This analysis structure is essentially a summarization of a professional paper by Fitzhugh (86) that thoroughly describes why such a prediction procedure results in “failed evidence.”
It is Fitzhugh's "failed evidence" concept that relates to Post 34 closed with the following:
Did WEiT, knowingly or unknowingly, commit a cardinal scientific error in the nature of a “syllogistic faux-naif?”
Basically, a syllogism is a method for arranging required components of an argument in a diagrammatic structure that insures the inclusion of required statements on which to base the argument and to help insure the arguments conclusion has conformed to several basic principles of logic.
It is the syllogism structure and logic that, in this post, is used to evaluate WEiT’s prediction examples.
One of the major “fulfilled predictions” addressed by WEiT involved the fossil Tiktaalik roseae:
One of the greatest fulfilled predictions of evolutionary biology — a transitional form between fish and amphibians. This is the fossil species Tiktaalik roseae —. (pages 35-38) [underlining substituted for original italicized text-other emphasis supplied]
Accompanying the discussion of a number of morphological traits that proved the fossil was a transitional form in its proper setting, WEiT stated:
Its discovery is a stunning vindication of the theory of evolution. (page 35) [emphasis supplied]
And:
— the most tangible evidence that evolution was true. (page 38) [emphasis supplied]
In short, this fossil was presented by WEiT as a sort of “poster child” as an example of the predictive successes of “Darwinian science.”
The logic literature abounds with treatments of syllogistic-styled arguments, but Fitzhugh’s paper is particularly relevant to the thrust of this post since Tiktaalik roseae was also the organism that Fitzhugh used as a “real world” example to support a more formal discussion fundamentally involving the differences between evidence and inference in evolutionary biology prediction efforts.
It is something of an understatement that Fitzhugh’s paper is “tedious” and by no means a subject for causal perusal, perhaps why it so seldom referenced in evolutionary biology literature, although other reasons will likely become apparent as WEiT’s view of fossil evidence (and presumably representing evolutionary biology's views) comes under the scrutiny of Fitzhugh’s paper.
Syllogistic-arranged logic is, as stated above, tedious to follow since the logic flow involves a tight sequence that requires more than a casual reading to fully comprehend the sequence.
Fitzhugh incorporates his analysis of “predictions,” based on the “recursive” use of observed phenomena to predict aspects of the same phenomena, within the logic of hypothesis and theory testing, thereby addressing WEiT’s requirement of testing as an integral requirement for determining the validity of scientific theories.
A contrary view of this post’s condemnation of WEiT’s supportive evidence for Darwinism’s validity must also be contrary to Fitzhugh’s syllogism-based explanations of hypothesis and theory testing --- that is the challenge for "skeptics" as addressed below.
Thus, a close reading of his syllogism examples, admittedly something of a challenge, must be the basis for such skepticism.
One subtle aspect of Fitzhugh’s treatment of ‘potential” versus “actual” hypothesis and theory testing (refer to the following summary of syllogism (14)) is the implications that the whole Darwinian process has no predictable power concerning the development of morphological diversity, which is acknowledged by WEiT by the following:
By predictions, I don’t mean that Darwinism can predict how things will evolve in the future. (page 17) [emphasis supplied]
If such be the case, then as discussed by Fitzhugh under the rules of logic, as described below in syllogism (14), expecting a definitive prediction of Tiktaalik’s morphological traits would fall under the same problem of impossibility, considering that, although not a “future” development, it would qualify as such because it is new and “future” forms are new.
When distilled to its fundamental concept, Fitzhugh’s paper points out the critical difference between evidence and inference, and as such, provides the rationale for determining that WEiT’s transitional sequence “fulfilled predictions” do not qualify as evidence that verifys Darwinian tenents but rather are inferences that have not been tested.
Fitzhugh's syllogism sequence begins with an example that illustrates why WEiT's evidence of "predictions fulfilled" cannot be adapted to a correctly constructed syllogism-styled prediction, and ends with an example of why an actual syllogism test of prediction based on correctly applied evidence, versus a potential syllogism test prediction, cannot be realistically performed.
Although paraphrasing or otherwise “explaining” or shortening his explanations would run the danger of creating misinterpretations, for those who are not inclined to delve into the particulars, the following summary of Fitzhigh's five syllogisms (and associated text) are offered.
If this "brief" of Fitzhugh's thoroughly discussed syllogisms is sufficient for the reader, at least as an initial introduction, the reader may wish to skip to Fitzhugh's discussion following syllogism (14) and this post's ending summary --- skip the gritty details that Fitzhugh uses to justify his conclusion in syllogism (14).
But should details be desired,his entire text involving Tiktaalik directly and his “contrived” example representing a Tiktaalik-type prediction, starting with the section labeled "Failed Evidence For Evolution," is presented complete as in Fitzhugh’s paper (with bold emphasis supplied).
Fitzhugh's syllogism sequence begins with syllogism (11) as an example that illustrates why WEiT's observations do not constitute valid predictions and ends with syllogism (14) as an example that illustrates why a syllogism structured prediction cannot be assembled for a true prediction test.
Syllogism (11) is the analytical form representing an “abductive” line of logic designed from a body of “Tiktaalik type” observations, with a confirmed hypothesis designed to verify the concept of natural selection.
Fitzhugh essentially states that the syllogism’s argument is insufficient to validate the hypothesis because it is “deductive,” (proceeds from a general observation to specific entities) and thus requires a different argument sequence as in syllogism (12a)
Syllogism (12a) essentially arranges the syllogism (11) information in a different argument order that adds a “predicted test consequence”, i.e., prediction of what new fossil will be found.
Fitzhugh explains that the syllogism’s deduction of test consequences is inadequate because nothing in the syllogism concerns statements of specific traits to be exhibited by the newly discovered fossil, i.e., the new fossil could exhibit any possible combination of traits.
Thus, new fossil forms are just new effects that need to be explained and thus cannot qualify as test evidence, thus requiring an additional change in the argument sequence, as in syllogism (12b).
Syllogism (12b), which is only illustrated with the new phrasing of the “predicted test consequences,” incorporates the specific traits that should characterize a newly discovered fossil for validation of the theory.
But this argument sequence is also invalid for reasons best left to Fitzhugh’s explanations, which leads to syllogism (13).
Syllogism (13) starts to more directly address why fossils such as Tiktaalik represent evidence to which a theory would be applied rather than evidence that could assess the theory’s validity.
Fitzhugh points out that the inadequacy of this syllogism’s argument lies in the lack of causal conditions descriptions in the syllogism’s premises—causal conditions that would need to be witnessed from which the tests consequences should be deducible.
These causal conditions to be witnessed are present conditions (rather than past conditions as in syllogisms (11), (12a), and (12b) which cannot be observed), and thus fossil evidence is ruled out which leaves future conditions to provide test results as added in syllogism (14).
Syllogism (14), which Fitzhugh introduces as potential test evidence, incorporates the essential element of an observed causal condition that points to what might be interpreted as “the” fatal logic error in WEiT’s “predictions fulfilled” examples and likely evolutionary biology’s insurmountable problem for validating Darwinism’s tenets — the syllogism argument specifies “Potential Test Consequences” as “occurrences of the trait should increase in the population into the future.”
The critical emphasis is on "Potential Test Consequences" that depend on "future observations" which eliminate the syllogism from consideration that it represents an argument for a test that will actually be performed.
Failed Evidence For Evolution [bold and underlining supplied throughout Fitzhugh’s text]
The most consistent point of view regarding the testing of either a theory in evolutionary biology or a phylogenetic hypothesis has been that predictions of particular organisms, or their characters, qualify as relevant test evidence (e.g. Wiley 1975; Barnosky and Kraatz 2007; Prothero 2007; contra Fitzhugh 2006a, 2008a). In other words, the same class of evidence that is used to infer hypotheses, as well as a theory such as natural selection, also stands as supporting evidence. A good example of this position is the discovery of ‘transitional forms’ in the fossil record. Consider the recent description of Tiktaalik roseae by Daeschler et al. (2006; see also Shubin et al. 2006), a fossil of a Devonian fish with pectoral fins intermediate in form between fins and limbs. In commenting on this find, Ahlberg and Clack (2006: 748) regard the fossil as significant because “it demonstrates the predictive capacity of palaeontology.” Similarly, T. roseae was cited in chapter one of the publication, Science, Evolution, and Creationism (National Academy of Sciences and Institute of Medicine 2008: 1, 3; see also Ayala 2006), within the section entitled, “The scientific evidence supporting biological evolution continues to grow at a rapid pace.” Using this species as their example, it is claimed that,
“A prediction from more than a century of findings from evolutionary biology suggests that one of the early species that emerged from the Earth’s oceans about 375 million years ago was the ancestor of amphibians, reptiles, dinosaurs, birds, and mammals. The discovery of Tiktaalik strongly supports that prediction. Indeed, the major bones in our own arms and legs are similar in overall configuration to those of Tiktaalik.
The discovery of Tiktaalik, while critically important for confirming predictions of evolution theory, is just one example of the many findings made every year that add depth and breadth to the scientific understanding of biological evolution.”
Is this fossil confirming evidence for “evolution theory?” Unfortunately, the answer is no. Tiktaalik roseae provides neither confirming evidence for an evolutionary transition from fishes to terrestrial tetrapods nor support for any of the theories within evolutionary biology. The following contrived example can make this evident.
Fitzhugh then demonstrates a general parallel with the Tiktaalik prediction with the following simple set of “contrived” fossil traits in the following illustration, which information is then analyzed in several syllogisms.
The fundamental goal of these syllogisms and associated discussions is to clearly draw a distinction between inference and evidence.
The illustration’s form D would represent the Tiktaalik fossil. The following Fitzhugh text format is listed in separated sentence-by-sentence sequence to perhaps more clearly illustrate the sequence logic.
A series of fossils are found from the dated strata shown in Figure 1A.
The oldest fossils are of individuals lacking lateral appendages or dorsal ornamentation,
whereas slightly younger fossils show the presence of one pair of appendages, and
individuals from the youngest strata have three pairs.
As well, members of the two youngest species have varying degrees of dorsal ornamentation.
But, there is a gap in the record, between 165 and 100 mya where no members of this group had been found thus far.
The phylogenetic hypothesis for these fossils (Fig. 1B) suggests the following two transformation series:
(a) absence of appendages ! [form a-us]
one pair of appendages ! [form b-us]
three pairs of appendages, [form c-us] and
(b) smooth dorsal margin ! [forms a-us and b-us]
one pair of dorsolateral protuberances ! [form c-us]
a row of five protuberances over the dorsum. [form d-us]
The actual inference of these hypotheses from the observations would have the following abductive form (cf. Fitzhugh 2005a, b, 2006a, b, 2008a, b, in press):
[11] Theory:
“descent with modification’ – if character x(0) exists among individuals of a reproductively isolated, gonochoristic or cross-fertilizing hermaphroditic population, and character x(1) originates by mechanisms a, b, c... n, and becomes fixed within the population by mechanisms d, e, f... n [= ancestral species hypothesis], followed by event or events g, h, i... n, wherein the population is divided into two or more reproductively isolated populations, then individuals to which descendant species hypotheses refer would exhibit x(1)
Observations (Fig. 1A):
(1) individuals to which species hypotheses b-us, c-us, and d-us refer have appendages in contrast to a convex ventrum as seen among individuals to which other species hypotheses refer;
(2) individuals to which species hypotheses c-us and d-us refer have dorsal protuberances in contrast to a convex dorsum as seen among individuals to which other species hypotheses refer
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Hypothesis (Fig. 1B):
(a-us (b-us (c-us d-us))), i.e.,
(1) ventral appendages originated by some unspecified mechanism(s) within a reproductively isolated population of individuals with a convex ventrum, and the condition became fixed in the population by some unspecified mechanism(s), followed by an unspecified event(s) that resulted in two reproductively isolated populations, i.e. members of species a-us and members of an ancestral species eventually leading to members of b-us, c-us, and d-us;
(2) dorsal protuberances originated by some unspecified mechanism(s) within a reproductively isolated population of individuals with a convex dorsum, and the condition became fixed in the population by some unspecified mechanism(s), followed by an unspecified event(s) that resulted in two reproductively isolated populations, i.e. members of species c-us and d-us.”
From the temporal distribution (Fig. 1A) and phylogenetic hypothesis (Fig. 1B), one might claim that specimens will be found in the 165 to 100 mya strata that exhibit appendages and dorsal surface features that are transitional to what has been found in earlier and later strata (Fig. 1C). Such a prediction, if found to be the case, would be claimed to provide notable evidential support for the phylogenetic hypothesis, and by extension the ability of evolutionary biology to steer us in the right direction when it comes to seeking ‘transitional forms.’ Upon further investigations of the 165 to 100 mya strata fossils are found, with two pairs of appendages and three dorsal protuberances. Such a finding is in accord with what was ‘predicted.’ But, does this new fossil serve as a legitimate test of the phylogenetic hypothesis? Does the finding increase the veracity of evolutionary biology, at least in the context of, say, natural selection? Let’s first consider the situation if it is the case that fossils are test evidence for the phylogenetic hypothesis in [11] (Fig. 1B). To assert that the discovery of some ‘transitional’ form in strata between 165 and 100 mya supports (a-us (b-us (c-us d-us))), that prediction would have to be a deductive consequence of the form shown in [8]. The deduction would, at a minimum, have the following appearance:
[12a] Theory:
“descent with modification” – if character x(0) exists among individuals of a reproductively isolated, gonochoristic or cross-fertilizing hermaphroditic population and character x(1) originates by mechanisms a, b, c... n, and becomes fixed within the population by mechanisms d, e, f... n [= ancestral species hypothesis], followed by event or events g, h, i... n, wherein the population is divided into two or more reproductively isolated populations, then individuals to which descendant species hypotheses refer would exhibit x(1)
Hypothesis:
(a-us (b-us (c-us d-us))), i.e.,
(1) ventral appendages originated by some unspecified mechanism(s) within a reproductively isolated population of individuals with a convex ventrum, and the condition became fixed in the population by some unspecified mechanism(s), followed by an unspecified event(s) that resulted in two reproductively isolated populations, i.e. members of species a-us and members of an ancestral species eventually leading to members of b-us, c-us, and d-us;
(2) dorsal protuberances originated by some unspecified mechanism(s) within a reproductively isolated population of individuals with a convex dorsum, and the condition became fixed in the population by some unspecified mechanism(s), followed by an unspecified event(s) that resulted in two reproductively isolated populations, i.e. members of species c-us and d-us
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Observations that led to the original inference of the hypothesis (Fig. 1A):
(1) individuals to which species hypotheses b-us through d-us refer have appendages in contrast to a convex ventrum as seen among individuals to which other species hypotheses refer; (2) individuals to which species hypotheses c-us and d-us refer have dorsal protuberances in contrast to a convex dorsum as seen among individuals to which other species hypotheses refer
“Predicted” test consequence, per Figure 1A:
Fossils of a ‘transitional’ form should be found in strata between 165 and 100 mya that have a number of appendages or dorsal protuberances that are intermediate to what are seen among members of species c-us and d-us (cf. Fig. 1C).
What should be noticed in this example is that the deduction is invalid insofar as the conclusion of the ‘predicted’ test consequence is not possible. The premises, especially hypothesis (a-us (bus (c-us d-us))), presents a series of causal conditions that, in conjunction with the theory of ‘descent with modification,’ account for the observed effects originally observed (Fig. 1A). From these premises there are no statements that could be derived that refer to specific properties of unobserved individuals. In point of fact, the premises do not preclude finding new fossils with any possible combination of characters. The consequence is that such fossils, if found, provide no relevant information that could assess the veracity of the hypothesis being tested. Additional fossil forms are simply newly observed effects also in need of explanation. The observations of new individuals cannot qualify as the test evidence for evaluating (a-us (b-us (cus d-us))) (Fitzhugh 2005a, b, 2006a, b, 2008a, b). The only valid statements that could be inferred from the premises in [12a], and would therefore function as potential tests of the hypothesis, would be those regarding effects that are direct and specific consequences of the causal events stated in the hypothesis, e.g.,
[12b] Correct predicted consequences:
Respective effects U, V, W,... n should be observed, indicating the causal events of character origin and fixation of appendages and dorsal protuberances in an ancestral population, and effects X, Y, Z,... n should be observed, indicating occurrences of causal events resulting in splittings of populations into separate, reproductively isolated groups.
Clearly, to speak of the testing of a phylogenetic hypothesis represented as a ‘cladogram’ (Fig. 1B, C) would not be possible given that such branching diagrams do not provide even sufficient specific details of the causal events one would be interested in testing. Inferring potential tests would only be possible once the different classes of events implied by such a diagram are fully explicated and replace the vaguely worded minor premise in [12a].
One of the inherent difficulties with proceeding to the next step of actually testing explanatory hypotheses is that the process can be severely constrained by the amount of time that has elapsed between the hypothesized events to be tested and the observed effects. There is the possibility that the ensuing span of time is sufficient to eliminate the kind of test evidence identified in [12b]. In such a situation, we might say a hypothesis remains ‘potentially testable,’ as opposed to ‘untestable.’ In other words, empirical observations might eventually be available under current conditions. An untestable hypothesis would be one in which the consequences previously deduced are entirely beyond scrutiny because the theory or associated background knowledge upon which it is based, in the form of auxiliary theories, allow for no conceivable conditions under which the consequences can be empirically verified or refuted. Such an instance will be discussed in the next section.
A more general consideration regarding the observations in Figure 1A in terms of ‘evidence’ for any of the theories in evolutionary biology, such as natural selection, genetic drift, etc., suffers the problem just encountered for hypothesis testing. As in the instances described earlier of the fossils of Tiktaalik roseae being regarded as evidence supporting evolution, the failure of this position is that it rests on the evidence to which a theory would be applied, not evidence that could actually assess the theory. From the observations in Figure 1A, for one to claim that new fossils provide supporting evidence for an evolutionary theory, say natural selection, would mean that the deductive argument would have the form,
[13] Natural selection theory:
in the event a novel, heritable character is derived as a consequence of mutation, and this character has a positive influence on fitness, then the character will become progressively prevalent in the population
“Causal” condition:
fossils that are members of a new species should be found in strata between 165 and 100 mya
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“Predicted” consequence:
individuals will exhibit conditions intermediate of those observed in earlier and later individuals.
What is apparent in this instance is that the inference is not valid. The conjunction of the two premises would not allow for the conclusion. More fundamental, the minor premise does not state the proper antecedent conditions from which the theory of natural selection could be subjected to testing (cf. [9]). As theories have the form, ‘given causal condition x, effect y will ensue,’ deducing potential test observations would necessitate that the minor premise state the causal conditions that would need to be witnessed, from which consequences should be deducible if the theory is true. Testing theories proceed from knowing the causal conditions in the present to the subsequent observations of effects. Notice that this condition differs substantially from what was shown in [10] and [12a/b] for hypothesis testing, where causal conditions were past events that cannot be observed, such that what must be obtained is evidence related as specifically as possible to those events. Rather than relying on fossils, which are the effects that have served as evidence for the abductive inferences of evolutionary theories and hypotheses, the proper inference of potential test evidence of the theory of natural selection would have the form,
[14] Natural selection theory:
in the event a novel, heritable character is derived as a consequence of mutation, and this character has a positive influence on fitness, then the character will become progressively prevalent in the population
Causal condition: a new, heritable trait is observed within a population, that potentially enhances relative fitness
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Potential Test consequence:
occurrences of the trait should increase in the population into the future.
The evidential requirements for testing evolutionary hypotheses and theories immediately preclude simply recording the occurrences of fossils or extant organisms. What are observed of organisms are properties that prompt the applications of a variety of theories in evolutionary biology, such that those properties could not recursively assess the explanatory import of the theories and hypotheses abductively applied to them. Far more careful consideration of the nature of test evidence is required.
The general nature of the problem addressed by Fitzhugh is addressed in the following material that constitutes parts of the paper’s introduction and various summarization statements.
The claim by biologists and ID advocates alike that observed effects can serve as ‘evidence’ supporting their alternative views suffers from a fundamental error – that of confusing the ‘evidence’ one uses as the basis for inferring a theory or hypothesis with the ‘evidence’ needed to critically assess either. It is a distinction Hanson (1958: 200, note 2, emphasis original; Achinstein 1970) recognized as too often ignored or denied as a consequence of the adoption of hypothetico-deductivism (H-D). There is,
”...the logical distinction between (1) reasons for accepting an hypothesis H, and (2) reasons for suggesting H in the first place. (1) is pertinent to what makes us say H is true, (2) is pertinent to what makes us say H is plausible. Both are the province of logical inquiry, although H-D theorists discuss only (1) saying that (2) is a matter for psychology or sociology – not logic. This is just an error....
We are discussing the rationale behind the proposal of hypotheses as possible explicantia. H-D theorists never raise the problem at all.”
A common consequence of not clearly acknowledging the logic of hypothesis and theory formation is that the ‘reasons’ in (1) and (2) are not recognized as being very different classes of evidence. Evidence used to infer some theory or hypothesis cannot recursively function as evidence supporting the very theories or hypotheses that have been inferred to account for that evidence. The goal of this paper is to provide a brief outline of how to avoid the common mistake of confusing evidence ‘suggesting’ a particular theory or hypothesis with the evidence for ‘accepting’ that theory or hypothesis. Establishing this distinction has the benefit of reorienting debate about evolution and ID back to the real issue: applying the accepted tenets of testing as the means of deciding the explanatory merits of theories (Sober 1999). This is not a matter of promoting any kind of demarcation criterion between science and non-science. As was suggested by Laudan (1983; see also Stamos 2007), rather than stressing demarcation, which might be a tentative proposition, we should judge claims on the basis of what can be provided in the way of supporting or refuting empirical evidence. As such, careful consideration is required to make the distinction stated by Hanson (1958), especially when comparing evolutionary biology and ID.
Evidence and Inference
Inference involves a relation between evidence and conclusion – evidence comprises the premises from which one infers a conclusion (Salmon 1984b). To speak of the support for a proposition is to refer back to the premises. For instance, in the classic example of deduction, ---.
Evolution and ID Cannot Be Defended Via Abductive Evidence
We can now to assess the popular claims that observed organisms, either extant or as fossil remains, provide evidence supporting any of the theories encompassed by evolutionary biology or ID. Representative arguments found in the evolutionary and ID literature will be examined next.
His “summary” perspectives included the following:
The standard within the various fields of science that allow for critical evaluations of theories and hypotheses is the process of testing.
Since this principle is recognized by WEiT (see opening WEiT quotes in Post 34), a central question is posed:
Do WEiT’s presentations of fulfilled predictions satisfy the concept of scientific testing
— the real issue is to identify what evidence can actually be provided for the support of refutation of a theory or hypothesis — to speak of testing means we once again invoke the term “evidence.”
What becomes critical is to recognize how “evidence” plays different roles in the acquisition of understanding. We have to differentiate between evidence that compels us to infer a particular theory or hypothesis from evidence that, in the context of testing, supports or refutes those claims.
— it is the theory (and relevant background knowledge) and effects that provide the basis for the hypothesis provided — . In other words, we have the “reasons for suggesting H in the first place.” These reasons, i.e., evidence, stand entirely separate from the “reasons for accepting ... H —.
In referring to one of the paper’s syllogism illustrations, Fitzhugh comments:
— the inference of potential tests of a theory stipulate conditions having the form of an experiment, where one must put themselves in a position of witnessing the “experimental causal conditions” as well as the subsequent “predicted consequence.” — An important consequence is that the effect(s) that prompted inference of the hypothesis in the first place could not then serve as test evidence of that hypothesis, much less could effects of the same class as those that led to the hypothesis.
This post's conclusions concerning the scientific adequacy of the general structure of WEiT's myriad of predictions as validation of Darwinism are perhaps most clearly conveyed by:
WEiT's perspective of criteria to which evidence via "prediction" must conform:
For a theory to be considered scientific, it must be testable and make verifiable predictions. That is, we must be able to make observations about the real world that either support it or disprove it. (Page 15) [emphasis supplied]
WEiT's perception of what evidence "prediction" must address:
The theory of natural selection has a big job — the biggest in biology. Its task is to explain how every adaptation evolved, step by step, from traits that preceded it. This includes not just body form and color, but the molecular features that underlie everything. (Page 119) [underlining substituted for the original italicized text-other emphasis supplied]
WEiT's perspective of what evidence "prediction" produces:
---it predicts what we should find in living or ancient species when we study them (page 17)
Within these three requirements, "things" to be explained by prediction include "what we should find" repeated from the second WEiT quote in this post.
— change in the fossil record;
— species dividing into two or more;
— species that link together major groups of suspected common ancestry;
— species that show genetic variation for many traits;
— cases of imperfect adaptation;
— see natural selection acting in the wild.
And the six "components" of Darwinism that WEiT also perceives must also be addressed by these foregoing predictions:
--- evolution, gradualism, speciation, common ancestry, natural selection, and nonselective mechanisms of evolutionary change. (page 3)
The implausibility of other WEiT predictions, designed iafter the general format of the Tiktaalik example for providing evidence that supports the validation of Darwinism tenets, is demonstrated by evaluating the prediction format under the logic illustrated in Fitzhugh's foregoing syllogisms, particularly syllogism (14).
In short, as stated by Fitzhugh:
But, does this new fossil serve as a legitimate test of the phylogenetic hypothesis? Does the finding increase the veracity of evolutionary biology, at least in the context of, say, natural selection?
--- such fossils, if found, provide no relevant information that could assess the veracity of the hypothesis being tested. Additional fossil forms are simply newly observed effects also in need of explanation.
Tiktaalik roseae provides neither confirming evidence for an evolutionary transition from fishes to terrestrial tetrapods nor support for any of the theories within evolutionary biology.
Since this post only treated a "generic" perspective of WEiT's prediction concepts, the question remains:
How did WEiT use its prediction examples to validate the tenets in its two lists, as summarizeed above?
Literature Cited
Fitzhugh, Kirk. Evidence for Evolution Versus Evidence for Intelligent Desigm: Parallel Confusions. Evolutionary Biology. Volume 37, Numbers 2-3, 1007.
