 Chitta Baral, Michael Gelfond, and Nelson Rushton (Baral et al. 2009) have developed a declarative language P-Log, which combines defeasible logic with Bayesian probability nets. They use Answer Set Prolog to provide the logical foundations. They make use of a version of the principle of indifference. Belief revision occurs by means of Bayesian conditioning. Baral et al. demonstrate that P-log can reason correctly about the Monty Hall problem and Simpson’s paradox. See Gelfond and Kahl 2014, pp. 235–270 for the syntax and semantics of P-log.