Combining Philosophers

All the ideas for Tertullian, Oliver,A/Smiley,T and C.I. Lewis

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

27 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
7791 The simplest of the logics based on possible worlds is Lewis's S5 [Lewis,CI, by Girle]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
14239 The empty set is usually derived from Separation, but it also seems to need Infinity [Oliver/Smiley]
14240 The empty set is something, not nothing! [Oliver/Smiley]
14241 We don't need the empty set to express non-existence, as there are other ways to do that [Oliver/Smiley]
14242 Maybe we can treat the empty set symbol as just meaning an empty term [Oliver/Smiley]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
14243 The unit set may be needed to express intersections that leave a single member [Oliver/Smiley]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
9358 There are several logics, none of which will ever derive falsehoods from truth [Lewis,CI]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
9357 Excluded middle is just our preference for a simplified dichotomy in experience [Lewis,CI]
5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
9364 Names represent a uniformity in experience, or they name nothing [Lewis,CI]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
14234 If you only refer to objects one at a time, you need sets in order to refer to a plurality [Oliver/Smiley]
14237 We can use plural language to refer to the set theory domain, to avoid calling it a 'set' [Oliver/Smiley]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
14245 Logical truths are true no matter what exists - but predicate calculus insists that something exists [Oliver/Smiley]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / g. Applying mathematics
14246 If mathematics purely concerned mathematical objects, there would be no applied mathematics [Oliver/Smiley]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
14247 Sets might either represent the numbers, or be the numbers, or replace the numbers [Oliver/Smiley]
10. Modality / A. Necessity / 2. Nature of Necessity
11002 Equating necessity with informal provability is the S4 conception of necessity [Lewis,CI, by Read]
10. Modality / A. Necessity / 11. Denial of Necessity
9362 Necessary truths are those we will maintain no matter what [Lewis,CI]
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
7803 Modal logic began with translation difficulties for 'If...then' [Lewis,CI, by Girle]
12. Knowledge Sources / A. A Priori Knowledge / 7. A Priori from Convention
9365 We can maintain a priori principles come what may, but we can also change them [Lewis,CI]
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
21500 We rely on memory for empirical beliefs because they mutually support one another [Lewis,CI]
21501 If we doubt memories we cannot assess our doubt, or what is being doubted [Lewis,CI]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
6556 If anything is to be probable, then something must be certain [Lewis,CI]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
21498 Congruents assertions increase the probability of each individual assertion in the set [Lewis,CI]
18. Thought / C. Content / 8. Intension
5828 Extension is the class of things, intension is the correct definition of the thing, and intension determines extension [Lewis,CI]
18. Thought / E. Abstraction / 2. Abstracta by Selection
9361 We have to separate the mathematical from physical phenomena by abstraction [Lewis,CI]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
9363 Science seeks classification which will discover laws, essences, and predictions [Lewis,CI]
29. Religion / B. Monotheistic Religion / 4. Christianity / d. Heresy
16713 Philosophers are the forefathers of heretics [Tertullian]
29. Religion / D. Religious Issues / 1. Religious Commitment / e. Fideism
6610 I believe because it is absurd [Tertullian]