15 ideas
| 18901 | Truthmakers are facts 'of' a domain, not something 'in' the domain [Sommers] |
| Full Idea: A fact is an existential characteristic 'of' the domain; it is not something 'in' the domain. To search for truth-making facts in the world is indeed futile. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'Existence') | |
| A reaction: Attacking Austin on truth. Helpful. It is hard to see how a physical object has a mysterious power to 'make' a truth. No energy-transfer seems involved in the making. Animals think true thoughts; I suspect that concerns their mental maps of the world. |
| 18904 | 'Predicable' terms come in charged pairs, with one the negation of the other [Sommers, by Engelbretsen] |
| Full Idea: Sommers took the 'predicable' terms of any language to come in logically charged pairs. Examples might be red/nonred, massive/massless, tied/untied, in the house/not in the house. The idea that terms can be negated was essential for such pairing. | |
| From: report of Fred Sommers (Intellectual Autobiography [2005]) by George Engelbretsen - Trees, Terms and Truth 2 | |
| A reaction: If, as Rumfitt says, we learn affirmation and negation as a single linguistic operation, this would fit well with it, though Rumfitt doubtless (as a fan of classical logic) prefers to negation sentences. |
| 18895 | Logic which maps ordinary reasoning must be transparent, and free of variables [Sommers] |
| Full Idea: What would a 'laws of thought' logic that cast light on natural language deductive thinking be like? Such a logic must be variable-free, conforming to normal syntax, and its modes of reasoning must be transparent, to make them virtually instantaneous. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'How We') | |
| A reaction: This is the main motivation for Fred Sommers's creation of modern term logic. Even if you are up to your neck in modern symbolic logic (which I'm not), you have to find this idea appealing. You can't leave it to the psychologists. |
| 18897 | Predicate logic has to spell out that its identity relation '=' is an equivalent relation [Sommers] |
| Full Idea: Because predicate logic contrues identities dyadically, its account of inferences involving identity propositions needs laws or axioms of identity, explicitly asserting that the dyadic realtion in 'x=y' possesses symmetry, reflexivity and transitivity. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'Syllogistic') |
| 18893 | Translating into quantificational idiom offers no clues as to how ordinary thinkers reason [Sommers] |
| Full Idea: Modern predicate logic's methods of justification, which involve translation into an artificial quantificational idiom, offer no clues to how the average person, knowing no logic and adhering to the vernacular, is so logically adept. | |
| From: Fred Sommers (Intellectual Autobiography [2005], Intro) | |
| A reaction: Of course, people are very logically adept when the argument is simple (because, I guess, they can test it against the world), but not at all good when the reasoning becomes more complex. We do, though, reason in ordinary natural language. |
| 18903 | Sommers promotes the old idea that negation basically refers to terms [Sommers, by Engelbretsen] |
| Full Idea: If there is one idea that is the keystone of the edifice that constitutes Sommers's united philosophy it is that terms are the linguistic entities subject to negation in the most basic sense. It is a very old idea, tending to be rejected in modern times. | |
| From: report of Fred Sommers (Intellectual Autobiography [2005]) by George Engelbretsen - Trees, Terms and Truth 2 | |
| A reaction: Negation in modern logic is an operator applied to sentences, typically writing '¬Fa', which denies that F is predicated of a, with Fa being an atomic sentence. Do we say 'not(Stan is happy)', or 'not-Stan is happy', or 'Stan is not-happy'? Third one? |
| 18894 | Predicates form a hierarchy, from the most general, down to names at the bottom [Sommers] |
| Full Idea: We organise our concepts of predicability on a hierarchical tree. At the top are terms like 'interesting', 'exists', 'talked about', which are predicable of anything. At the bottom are names, and in between are predicables of some things and not others. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'Category') | |
| A reaction: The heirarchy seem be arranged simply by the scope of the predicate. 'Tallest' is predicable of anything in principle, but only of a few things in practice. Is 'John Doe' a name? What is 'cosmic' predicable of? Challenging! |
| 18900 | Unfortunately for realists, modern logic cannot say that some fact exists [Sommers] |
| Full Idea: Unfortunately for the fate of realist philosophy, modern logic's treatment of 'exists' is resolutely inhospitable to facts as referents of phrases of the form 'the existence or non-existence of φ'. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'Realism') | |
| A reaction: Predicate logic has to talk about objects, and then attribute predicates to them. It tends to treat a fact as 'Fa' - this object has this predicate, but that's not really how we understand facts. |
| 13127 | Categories can't overlap; they are either disjoint, or inclusive [Sommers, by Westerhoff] |
| Full Idea: Fred Sommers, in his treatment of types, says that two ontological categories cannot overlap; they are either disjoint, or one properly includes the other. This is sometimes referred to as Sommers' Law. | |
| From: report of Fred Sommers (Types and Ontology [1963], p.355) by Jan Westerhoff - Ontological Categories §24 | |
| A reaction: The 'types', of course, go back to Bertrand Russell's theory of types, which is important in discussions of ontological categories. Carnap pursued it, trying to derive ontological categories from grammatical categories. 85% agree with Sommers. |
| 19722 | We could know the evidence for our belief without knowing why it is such evidence [Mittag] |
| Full Idea: While one might understand the proposition entailed by one's evidence, one might have no idea how or why one's evidence entails it. This seems to imply one is not justified in believing the proposition on the basis of one's evidence. | |
| From: Daniel M. Mittag (Evidentialism [2011], 'Evidential') | |
| A reaction: An example might be seen if a layman tours a physics lab. This looks like a serious problem for evidentialism. Once you see why the evidence entails the proposition, you are getting closer to understanding than to knowledge. Explanation. |
| 19723 | Evidentialism can't explain that we accept knowledge claims if the evidence is forgotten [Mittag] |
| Full Idea: If one came to believe p with good evidence, but has since forgotten that evidence, we might think one can continue to believe justifiably, but evidentialism appears unable to account for this. | |
| From: Daniel M. Mittag (Evidentialism [2011], 'Forgotten') | |
| A reaction: We would still think that the evidence was important, and we would need to trust the knower's claim that the forgotten evidence was good. So it doesn't seem to destroy the evidentialist thesis. |
| 19720 | Evidentialism concerns the evidence for the proposition, not for someone to believe it [Mittag] |
| Full Idea: Evidentialism is not a theory about when one's believing is justified; it is a theory about what makes one justified in believing a proposition. It is a thesis regarding 'propositional justification', not 'doxastic justification'. | |
| From: Daniel M. Mittag (Evidentialism [2011], 'Preliminary') | |
| A reaction: Thus it is entirely about whether the evidence supports the proposition, and has no interest in who believes it or why. Knowledge is when you believe a true proposition which has good support. This could be internalist or externalist? |
| 19721 | Coherence theories struggle with the role of experience [Mittag] |
| Full Idea: Traditional coherence theories seem unable to account for the role experience plays in justification. | |
| From: Daniel M. Mittag (Evidentialism [2011], 'Evidence') | |
| A reaction: I'm inclined to say that experience only becomes a justification when it has taken propositional (though not necessarily lingistic) form. That is, when you see it 'as' something. Uninterpreted shape and colour can justify virtually nothing. |
| 18898 | In standard logic, names are the only way to refer [Sommers] |
| Full Idea: In modern predicate logic, definite reference by proper names is the primary and sole form of reference. | |
| From: Fred Sommers (Intellectual Autobiography [2005], 'Reference') | |
| A reaction: Hence we have to translate definite descriptions into (logical) names, or else paraphrase them out of existence. The domain only contains 'objects', so only names can uniquely pick them out. |
| 1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |
| Full Idea: The Egyptians were the first to claim that the soul of a human being is immortal, and that each time the body dies the soul enters another creature just as it is being born. | |
| From: Herodotus (The Histories [c.435 BCE], 2.123.2) |