Hi,
> > What this highlights for me is the idea that NARS truth values attempt > > to reflect the evidence so far, while probabilities attempt to reflect > > the world > I agree that probabilities attempt to reflect the world > . > > Well said. This is exactly the difference between an > experience-grounded semantics and a model-theoretic semantics. I don't agree with this distinction ... unless you are construing "model theoretic semantics" in a very restrictive way, which then does not apply to PLN. If by model-theoretic semantics you mean something like what Wikipedia says at http://en.wikipedia.org/wiki/Formal_semantics, *** *Model-theoretic semantics<http://en.wikipedia.org/w/index.php?title=Model-theoretic_semantics&action=edit&redlink=1> * is the archetype of Alfred Tarski<http://en.wikipedia.org/wiki/Alfred_Tarski>'s semantic theory of truth<http://en.wikipedia.org/wiki/Semantic_theory_of_truth>, based on his T-schema <http://en.wikipedia.org/wiki/T-schema>, and is one of the founding concepts of model theory<http://en.wikipedia.org/wiki/Model_theory>. This is the most widespread approach, and is based on the idea that the meaning of the various parts of the propositions are given by the possible ways we can give a recursively specified group of interpretation functions from them to some predefined mathematical domains: an interpretation<http://en.wikipedia.org/wiki/Interpretation_%28logic%29>of first-order predicate logic <http://en.wikipedia.org/wiki/First-order_predicate_logic>is given by a mapping from terms to a universe of individuals <http://en.wikipedia.org/wiki/Individual>, and a mapping from propositions to the truth values "true" and "false". *** then yes, PLN's semantics is based on a mapping from terms to a universe of individuals, and a mapping from propositions to truth values. On the other hand, these "individuals" may be for instance **elementary sensations or actions**, rather than higher-level individuals like, say, a specific cat, or the concept "cat". So there is nothing non-experience-based about mapping terms into a "individuals" that are the system's direct experience ... and then building up more abstract terms by grouping these directly-experience-based terms. IMO, the dichotomy between experience-based and model-based semantics is a misleading one. Model-based semantics has often been used in a non-experience-based way, but that is not because it fundamentally **has** to be used in that way. To say that PLN tries to model the world, is then just to say that it tries to make probabilistic predictions about sensations and actions that have not yet been experienced ... which is certainly the case. > Once > again, the difference in truth-value functions is reduced to the > difference in semantics, what is, what the "truth-value" attempts to > measure. Agreed... Ben G ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=114414975-3c8e69 Powered by Listbox: http://www.listbox.com
