Combining Texts

All the ideas for 'Summa totius logicae', 'On the Conservation of Force' and 'Logical Consequence'

expand these ideas     |    start again     |     specify just one area for these texts


19 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
From an impossibility anything follows [William of Ockham]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
A proposition is true if its subject and predicate stand for the same thing [William of Ockham]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Ockham had an early axiomatic account of truth [William of Ockham, by Halbach]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Validity is explained as truth in all models, because that relies on the logical terms [McGee]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Natural language includes connectives like 'because' which are not truth-functional [McGee]
5. Theory of Logic / G. Quantification / 1. Quantification
The word 'every' only signifies when added to a term such as 'man', referring to all men [William of Ockham]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Second-order variables need to range over more than collections of first-order objects [McGee]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
An ontologically secure semantics for predicate calculus relies on sets [McGee]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logically valid sentences are analytic truths which are just true because of their logical words [McGee]
5. Theory of Logic / K. Features of Logics / 3. Soundness
Soundness theorems are uninformative, because they rely on soundness in their proofs [McGee]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
The culmination of Euclidean geometry was axioms that made all models isomorphic [McGee]
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
Just as unity is not a property of a single thing, so numbers are not properties of many things [William of Ockham]
7. Existence / A. Nature of Existence / 3. Being / g. Particular being
The words 'thing' and 'to be' assert the same idea, as a noun and as a verb [William of Ockham]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
Universals are single things, and only universal in what they signify [William of Ockham]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
If essence and existence were two things, one could exist without the other, which is impossible [William of Ockham]
19. Language / D. Propositions / 4. Mental Propositions
Some concepts for propositions exist only in the mind, and in no language [William of Ockham]
19. Language / F. Communication / 2. Assertion
A maxim claims that if we are allowed to assert a sentence, that means it must be true [McGee]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / a. Energy
Helmholtz used 'energy' to mathematically link heat, light, electricity and magnetism [Helmholtz, by Watson]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
All forces conserve the sum of kinetic and potential energy [Helmholtz, by Papineau]