One atheist objection I've run across goes like this: the more specific a claim, the more antecedently improbable the claim. There's an inverse relation between specificity and probability. So, for instance, Christian theism is more antecedently improbable than mere theism.
To which I'd respond:
i) For anything to exist, there must be a minimum threshold of complexity. So it's artificial to speak in the abstract about the prior probability of specific claims, as if something simpler is more likely to exist or occur than something more complex. Reality isn't incrementally reducible to zero.
By that logic, it's more antecedently probable that nothing whatsoever exists. But if nonexistence is the default assumption, why does anything exist? For that matter, probability theory is quite complex. Does that make it antecedently improbable that probability theory exists? But it takes probability theory to probabilify anything. So it can't be self-referential.
ii) Even assuming for argument's sake that the principle is true, it's misleading inasmuch as a more specific claim may have more specific evidence than a less specific claim. Christian theism may have a lot more evidence than mere theism.
1. By that logic, isn't materialistic atheism less probable than generic atheism?
ReplyDelete2. Depends how terms like specificity and probability are defined. A Merriam Webster or Oxford English Dictionary definition won't cut it. Too simplistic. For example, physicians need to determine whether a patient has or doesn't have a particular disease (e.g. lupus). However, that in turn depends on other variables. That is, whether it's true a patient has a disease depends on whether other variables are true. Conditional probability. So, suppose we consider Bayes’ theorem as a mathematical method to describe the post-test probability of a disease by combining the pre-test probability, specificity, and sensitivity. As such, if, say, the specificity of a test is defined as = true negatives / (true negative + false positives), which is how it is normally defined in medical statistics, then the specificity could range from 0%-100%. If the specificity of a test is low (e.g. 10%), then the test won't be able to accurately detect true negatives, whereas if the specificity of a test is high (e.g. 90%), then it will be able to detect true negatives. In short, there's more than one factor in play, and how we define our terms can impact our findings.
Also, doesn't evolution have some highly specific claims?
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