Combining Texts

All the ideas for 'Issues of Pragmaticism', 'First-Order Logic' and 'Epistemology'

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


15 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
There are three different standard presentations of semantics [Hodges,W]
I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
A 'set' is a mathematically well-behaved class [Hodges,W]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
The phenomenalist says that to be is to be perceivable [Cardinal/Hayward/Jones]
Linguistic phenomenalism says we can eliminate talk of physical objects [Cardinal/Hayward/Jones]
If we lack enough sense-data, are we to say that parts of reality are 'indeterminate'? [Cardinal/Hayward/Jones]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
Primary qualities can be described mathematically, unlike secondary qualities [Cardinal/Hayward/Jones]
An object cannot remain an object without its primary qualities [Cardinal/Hayward/Jones]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
My justifications might be very coherent, but totally unconnected to the world [Cardinal/Hayward/Jones]
19. Language / A. Nature of Meaning / 1. Meaning
The meaning or purport of a symbol is all the rational conduct it would lead to [Peirce]