03-17-12: Geoffkait
If we default to the most skeptical opinions, those with the narrowest definition of the "finite bounds of plausibility," how will that affect progress in many fields of human endeavor? Will we harken back to the dark ages when folks were persecuted for beliefs or abilities that lay outside the norm?
I can say with supreme confidence that Als use of the phrase finite bounds of plausibility does not reflect an attitude that harkens back to the dark ages when folks were persecuted for beliefs or abilities that lay outside the norm. You are strawmanning, again, Geoff, and now at preposterous levels. And targeting Al, who is widely regarded as the Exemplar of Audiogon contributors, is strategic suicide. You just multiplied your opponents by 10.
03-17-12: Tbg
Almarg, the only real question is do we all agree as to what is implausible and on how implausible it needs to be to be rejected a priori.
03-17-12: Almarg
The real issue, as both of you alluded to, is where to draw the line between plausibility and implausibility. Obviously the choice of where to draw that line will generally be subjective, debatable, and imprecise."
I respectfully disagree with you, Tbg, that we all need to agree on where to locate the line between what is plausible and implausible. That is partly because, as Al points out, the line is subjective, debatable, and imprecise.
Having said that, the line is not ALTOGETHER subjective, debatable, and imprecise. In other words, there are quite reliable methods for assessing the *prima facie* plausibility of a theory or explanation. Here are some of the considerations
1. Conformity to a recognized Model of Explanation. By this I mean essentially what I wrote in my post on 3/15:
Nearly all scientifically valid explanations are nomological, mechanistic, or teleological. That is to say, they explain events or entities in terms of underlying LAWS, MICROSTRUCTURE, or FUNCTIONS, respectively. Physics is the paradigmatic example of nomological explanation. Chemistry is the paradigmatic example of mechanistic explanation. Biology is the paradigmatic example of teleological explanation.
Explanations that are presented as scientific, but are neither nomological nor mechanistic nor teleological, are prima facie implausible. Even REVOLUTIONARY theories like General Relativity conform to a recognized Model of Explanation. Geoffs explanations for Machina Dynamica products do not.
2. A CAUSAL relationship between the explanation and the phenomenon to be explained. Prima facie plausible explanations provide a causal relationship between the thing to be explained (the explanandum) and the thing that does the explaining (the explanans). Geoffs explanations do not.
3. A large Circle of Justification between the theory and data. To some extent, there is always a circular relationship between theory and data, in that the theory provides reason to believe the data and the data provides reason to believe the theory. What distinguishes good explanations from bad ones is that good explanations have LARGE Circles of Justification. That is to say, they involve LOTS of data and LOTS of theory. As the data and the theory become sparser and sparser, and the Circle of Justification becomes smaller and smaller, the explanations that employ that data/theory become more and more questionable. The worst kind of explanation is one in which the ONLY reason to believe the data is provided by the theory, and the ONLY reason to believe the theory is provided by the data. In that case, the explanation is simply AD HOC. For an example of an ad hoc explanation, see any of Geoff's explanations.
4. Entailed predictions. Prima facie plausible explanations entail predictions. This is true even of REVOLUTIONARY explanations. For example, when Einstein created/discovered General Relativity, one of the predictions it entailed was Gravitational Lensing, i.e., the bending of light around supermassive objects like stars, so that you can see whats behind them. That prediction was famously confirmed when Gravitational Lensing was discovered to be real, lending tremendous credibility to General Relativity. So far as I can tell, Geoffs explanations entail no predictions whatsoever.
5. Parsimony. Everybody knows this one. Suffice to say, it doesnt look like this.
6. Independent Corroboration. So far as I am aware, NONE of Geoffs explanations have been independently corroborated. As discussed by Cbw and me in earlier posts, the standard of REPRODUCIBILITY is the one thing ALL scientifically valid explanations have in common.
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None of these considerations are definitive determinants of an explanations validity or truthfulness, but taken together, they provide a VERY reliable guide to assessing an explanations prima facie plausibility. And equally important, none of these considerations eliminates the possibility of REVOLUTIONARY explanations.
I suspect that most or all of the above considerations underlie Als assessments of prima facie plausibility. Perhaps common sense isnt the right term. Maybe its more like informed sense. That is something even more valuable.
Bryon