Michael Prescott’s readers responded haveto my latest series of critical remarks on their earlier comments. Here I’m only going to comment on one reader’s response, the first in the thread.

The reader writes:

I have read the article by Sudduth and I think he will not be satisfied until someone develops a survival hypothesis that make predictions that can be falsified, that is, according to him, the key is not what observations could confirm my hypothesis but what observations would falsify my hypothesis, following the Popperian epistemology.

He goes on to say:

However, I do not accept the epistemological approach of Sudduth, because he is a deductive approximation based on the work of Popper: postulate hypothesis draw their predictions and observe if the hypothesis is falsified, but the hypothesis of survival is part of the abductive and inductive hypotheses: observe a number of phenomena and infer the simplest hypothesis that relates to everyone. And here the simplest hypothesis that relates OBEs, NDEs, apparitions, mediumship and people seem to remember their past lives is a determined survival hypothesis, ie that there is a vehicle of the psyche that remains after biological death and it can appear, own certain individuals, rebirth and remember their previous incarnations lives.

RESPONSE: I am not a Popperian, nor do my criticisms of survival arguments, unfortunately misrepresented by the reader, depend on Popperian epistemology. In fact, I explicitly reject Popperian epistemology, which I regard as largely misguided and corrected by subsequent philosophers of science.

The core problem with survival arguments is not lack of falsifiability. It’s relatively easy to formulate a survival hypothesis that can be falsified. If we recall the Duhem-Quine thesis (to which I’ve referred several times now), it becomes clear that any hypothesis is easily falsifiable, including survival. I can, for example, easily falsify the God-with-purple-objects-fetish hypothesis: the world was created by a supremely powerful being who wanted everything to be purple. Similarly, I can easily insulate any hypothesis from falsification. The God-with-purple-objects-fetish hypothesis is not falsified by there being non-purple objects because he only wanted some things to be purple, as he was actually in fetish recovery when he made the world. There are dozens of survival hypotheses that can be falsified (or rendered immune to this), and I’ve explained how this would work. So I’m actually quite satisfied at this juncture.

The core problem, to repeat, is lack of independent support for auxiliary hypotheses needed to generate predictive consequences (or explanatory salience). To be sure, this creates problems for falsifying hypotheses, but falsification is not the core problem. The problem of auxiliary hypotheses infects survival arguments in all their classical formulations, including inference to best explanation formulations (which the commenting reader favors). What is essential to all formulations of survival arguments is the idea that the survival hypothesis is supposed to lead us to expect (deductively or probabilistically) the observational data. This is essential whether we’re construing the survival argument abductively (as an inference to best explanation) or in terms of non-explanatory confirmation criteria. This requirement leads right to the problem of auxiliary hypotheses, which, I should repeat, is completely independent of Popperian epistemology.

my interview with Jime Sayaka As for the survival hypothesis being the most simple explanation of the data, I’ve yet to see a single survivalist make this argument in the light of the auxiliary hypothesis requirement. Survivalists routinely make the mistake of comparing a simple survival hypothesis (which has minimal or zero explanatory power) with robust alternatives (that is, alternatives that require various auxiliary hypotheses), and then they argue that the survival hypothesis is the simpler hypothesis. Naturally, survival wins using this strategy, but the strategy is a logical sleight of hands, as I pointed out inearlier this year. Survivalists need to show that a robust survival hypothesis is more simple than robust alternatives. This has yet to be done, largely because survivalists ignore their dependence on auxiliary hypotheses. So I regard all simplicity arguments as a bit of a cheat.

Finally, whether the appeal to simplicity has any explanatory or evidential value will depend on the particular explanatory or confirmation model we assume. That being said, it’s generally the case that simplicity is only one determinant of explanatory power (or evidential weightings in confirmation models), and it’s probably the least significant given the elastic nature of the criterion. Like the appeal to fit with background knowledge, survivalists hang heavy arguments on a very thin and loose nail.

Most importantly, it’s utterly premature to appeal to the survival hypothesis being the simplest explanation of the data until one first shows that the survival hypothesis *explains* anything at all. Simplicity is a “criterion of choice,” meaning that we appeal to it when our explanatory candidates are dead even in other respects, for example, predictive power. Survivalists assume that survival explains the data. They never really show this. At best they show that other hypotheses do not explain the data. To show that survival explains would burden survivalists with the baggage of auxiliary hypotheses.

I consider appeals to simplicity as, in principle, no different from appeals to “fit with background knowledge” and the alleged “failure of explanatory competitors,” a strategy of argument that attempts to circumvent requirements for the genuine testing of an ostensible empirical hypothesis. It distracts from the core issues and core deficiencies of hypotheses. When your hypothesis either explains or predicts nothing, shift the focus to the alleged defects of competing hypotheses and make your positive case, to the extent you have one, based on thin criteria like simplicity and fit with background knowledge. This is usually a sign that we’re dealing with a metaphysical hypothesis that’s parading as an empirical one. Metaphysical hypotheses have a wonderful way of accommodating any data you wish. So-called empirical arguments for survival are exactly like this. They are great examples of ex post facto reasoning or evidence retrofitting, which of course can serve explanatory competitors just as well (or poorly, as the case may be). If the empirical world had been any other way, you could run exactly the same argument. One certainly doesn’t have to be a Popperian to find this form of reasoning objectionable.

Michael Sudduth

Related Readings in Philosophy of Science:

“Reintroducing Prediction to Explanation,” Heather Douglas,in Philosophy of Science, 2009, 76: 444-463.

Elliott Sober and Christopher Hitchcock, “ Prediction Versus Accommodation and the Risk of Overfitting .“ British Journal for the Philosophy of Science 2004, 55: 1-34.