ID, Bayesian inferences and the Priors of MN

I was thinking about ID as an inference from data ( not as a Scientific hypothesis or theory) and wondering whether the design inference can be presented in Bayesian terms. On googling it i found an article that does just that. It seems to address all the issues connected to a design inference. The equation and definition of terms are as below-

H : the organism was designed by an intelligent creator
E : the organism looks like it was designed by an intelligent creator
E|H : if the organism was ID’d, the plausibility it looks ID’d.
E|~H : if the organism was not ID’d (e.g. it evolved), the plausibility it looks ID’d.

There is even a table showing how assigning different probabilities to different beliefs does to the final inference.

Now the question is, what is the impact of MN on P(H) and P(~H). It seems MN automatically ascribes a low value to P(H) and a high value to P(~H).

Link to the article : a bayesian analysis of intelligent design | AI and Social Science – Brendan O'Connor


It seems you’re mixing up MN and PN. MN says nothing about H.


Wouldn’t MN assume P(H); the probability that an organism was designed as zero… it might be not a truth claim in MN, but MN works under the assumption that P(H) is zero.

No, MN says that science can only study natural causes. It doesn’t say that supernatural events are impossible, or even that design (by natural means) can’t be studied by science.

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If MN only addresses natural means when making inferences, in the equation above,MN must consider P(H) as negligibly small by necessity.
This is a direct result of using MN.

Again, MN is about what science can study, not what must be the case. You’re also conflating “design” with “supernatural”, which I think the DI and company would disagree with.


I am talking about inferences. Its a fact that Science makes inferences regarding how organisms become the way they are.

I don’t see how an inference can be made without minimizing P(H) (in the case discussed above).

Can you show me what the Bayesian inference would look like if evolution is used to explain why the eye is the way it is.
I think any such inference would have a possibility that the eye has been designed which is ignored.

The possibility of the eye being supernaturally designed is ignored by science, since it falls outside of MN. That doesn’t mean that the possibility itself is ignored in principle.

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Actually we infer design in nature, including biology, all the time. MN does not rule out design. It rules out divine design.


I am not saying it’s ignored in principle… only that it’s ignored in practise… so the process of the inference using MN would assume P(H) is minimal as far as I can see.
Frankly in a Bayesian inference, I don’t see how PN and MN can look different.

So in the ID example above… P(H) in MN would be the probability that aliens created life?

What would the inference look like in practise?

It’s not somehow specific to a bayesian inference - when it comes to actually practicing science MN and PN are identical, but outside the lab they’re quite different. If you know of a way to practice science without MN, do tell.

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That’s the point I was making.

Based on your comment… let me extend the question…

Do you think there is any kind of inductive reasoning method in which MN and PN will give different inputs?
If so, what is wrong in thinking that there is an intrinsic bias and that every Scientific inference will favor PN?

@Eddie, I would love to get your input.

Nothing. You’re right: in practice, within science, MN amounts to PN.

If I were a philosophical naturalist, and wanted completely to domesticate (tame) theists and other troublemakers, I would persuade them that MN is necessary to the orderly practice of science. They can believe what they want about the universe on their own time.

In the lab, however, or at the bench, naturalism rules. MN or get out.


I take it you disagree then? Can you explain how to incorporate supernatural phenomena into science at the bench?

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I don’t know what “supernatural” means.

Science needs testability. But MN goes well beyond that, and limits the possible ontology of science to causes ultimately derived bottom-up from physics.

If “intelligence” is real, however, and does not derive ultimately from physics, then MN rules out a possible cause prior to testing. That’s bad news for open inquiry.


It’s the thing that MN says we should avoid considering when performing science. MN doesn’t preclude testing for naturalistic design, I just don’t think any good tests for design have been proposed.


“Supernatural” = avoid this when doing science.

“Science” = empirical inferences that avoid the supernatural.

Not helpful, definition-wise.

Saying that no one has yet devised a test for design hypotheses is NOT using MN as rule. It is saying that existing design hypotheses are immature or underdeveloped, and I might well agree with that.

MN only works if it’s a rigorously applied rule. Anything less is just ordinary reasoning.


Let me rephrase then: what phenomena do you think are amenable to scientific study that are currently being dismissed as violating MN?