Reductionism, as espoused by Hawking [32], is defined as the notion that the concatenated ``theory of everything,'' required by the fourth characteristic of positivist knowledge (section 2.1.4,) will take the form of the laws of physics10. Indeed, it has been pointed out [53] that Hawking [32] appears to propose a stronger version of reductionism, in which it will be the presently accepted laws of physics, with their predictive ability extended by more powerful computers and mathematical techniques, which eventually explain the results of all disciplines.
The Bayesian model of reductionism depends on what is meant by ``the form of the laws of physics.'' If taking the form of the laws of physics means being sufficiently unambiguous to be capable of making testable predictions, and failing to contradict postulates of simpler disciplines, in which one believes simultaneously, then reductionism is simply phenomenalism (section 2.1.1,) along with the prohibition on self-contradictory theories (section 2.1.4.) If, on the other hand, taking the form of the laws of physics means relating observable quantities through equations in a mathematical language, into which not all possible natural-language postulates can be translated, then it can be argued that reductionism is insisting on the assignment of zero prior probabilities to the un-translatable natural-language theories, rendering reductionism, with respect to these theories, an example of logical probability11(section 3.1.) A distinction between these two forms of reductionism is also discussed by Anderson [1], who names the former ``reductionism,'' and the latter ``constructionism.''