“Inference to be best explanation” is an illegitimate epistemology.
Abduction, sometimes called “inference to the best explanation“, is appropriate as a tool within science for identifying and submitting hypotheses for testing and potential falsification, but it is falls far short of the rigor required for epistemic integrity.
Consider a robbery in which a heavy safe has been removed from a normally locked office. One hundred individuals have keys to the door of the office. The strongest among those one hundreds individuals is Bob who can lift slightly more than the others. All else being equal, Bob becomes the best explanation. Within an epistemology that considers “inference to the best explanation” a legitimate reason to arrive at epistemic conclusions, Bob took the safe.
This abductive reasoning (also called retroduction) is the foundation of the epistemologies of a significant minority of Christians, if not the majority. Instead of mapping the degree of mapping certainty along the epistemic gradient to the degree of evidential certainty along the evidential gradient, Millions instead simply identify the most likely conclusion, and flip a switch from disbelief to an unnuance belief.
But rational belief is gradient. Identifying the best explanation, and making a binary conclusion that this best explanation is the explanation we will adopt is irrational. Rational belief requires that we do nothing less than map our degree of belief to the degree of the relevant evidence.
Yet millions, especially within theism, are taught that if explanation X is the best explanation, they are warranted in adopting that explanation as a binary conclusion.
“Inference to the best explanation” is only legitimate as an experimental design tool, and has no place in the epistemology of a rational mind.