A person, state, or other entity capable of making informed reason and evidence-based decision-making without the undue interference of non-evidential or non-reason based influences and/or processes (such as but not limited to cognitive biases, emotional fallacies, coercion) and who uses such thinking in making their decisions.
There are degrees of rationality that an entity exhibits corresponding to how often such thinking is used to make decisions. This concept is not in conflict with the narrower concept of a rational actor as understood through Rational Choice Theory - in fact, it is coterminous with and helps to flesh out that concept.
This is epistemic rationality and rationality as understood in the cognitive sciences, artificial intelligence, decision-making, formal epistemology, belief revision, etc. (though it is not a comprehensive articulation).
Emotion and Reason are required for correct, useful, inference-making otherwise we'd end up mostly in scenarios like that depicted by Buridan's Ass - as identified by Damasio and David Hume.
(1) Accurate, factual, trustworthy. E.g. - it must be derived from at least one or more of the following:
(a) Factual - demonstrably true through deductive proof, empirical (inductive or scientific) test; (b) Well-corroborated - verified or confirmed through numerous tests, sources, and information; (c) Provably (deductively) true; (d) Intersubjective invariance - what is common between first-person perspectives; (e) A correct, abductive, inference - what is reasonably the best, non-monotonic, explanation for an observed phenomena; (f) Highly probable - per (a); (g) Analytically true - per (c and a);
(2) Safe. E.g. - the information, content, and representation must be the minimally harmful implementation (within reason).
(3) Best. E.g. - the information, content, and representation must be the most useful with respect to specific use-case (within reason). Per (1) above, the best information is derived from satisfying the most number of the listed sources from which the information is derived.
(4) Consistent. E.g. - the information is logically consistent within the logical framework in which it is assessed (i.e. - quantum logics reject the law of distributivity).
(5) Clear. E.g. - The information is clear, simply put, and unambiguous.
(6) Improved. E.g. - The information is corrected in light of error and updated in case of absent information.
A rational actor will make more rational decisions by having and correctly using (a) greater amounts of good information and (b) having higher quality good information.
This is a well-confirmed and corraborated hypothesis.
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