Combining Texts

All the ideas for 'Logical Pluralism', 'On boundary numbers and domains of sets' and 'Travels in Four Dimensions'

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


56 ideas

3. Truth / A. Truth Problems / 1. Truth
Some truths have true negations [Beall/Restall]
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
A truthmaker is an object which entails a sentence [Beall/Restall]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
(∀x)(A v B) |- (∀x)A v (∃x)B) is valid in classical logic but invalid intuitionistically [Beall/Restall]
4. Formal Logic / E. Nonclassical Logics / 5. Relevant Logic
Excluded middle must be true for some situation, not for all situations [Beall/Restall]
It's 'relevantly' valid if all those situations make it true [Beall/Restall]
Relevant logic does not abandon classical logic [Beall/Restall]
Relevant consequence says invalidity is the conclusion not being 'in' the premises [Beall/Restall]
A doesn't imply A - that would be circular [Beall/Restall]
Relevant logic may reject transitivity [Beall/Restall]
4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
Free logic terms aren't existential; classical is non-empty, with referring names [Beall/Restall]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Zermelo showed that the ZF axioms in 1930 were non-categorical [Zermelo, by Hallett,M]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / h. Axiom of Replacement VII
Replacement was added when some advanced theorems seemed to need it [Zermelo, by Maddy]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic studies consequence; logical truths are consequences of everything, or nothing [Beall/Restall]
Syllogisms are only logic when they use variables, and not concrete terms [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
The view of logic as knowing a body of truths looks out-of-date [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Logic studies arguments, not formal languages; this involves interpretations [Beall/Restall]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
The model theory of classical predicate logic is mathematics [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
There are several different consequence relations [Beall/Restall]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
A sentence follows from others if they always model it [Beall/Restall]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall]
5. Theory of Logic / L. Paradox / 3. Antinomies
The antinomy of endless advance and of completion is resolved in well-ordered transfinite numbers [Zermelo]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / d. The Preface paradox
Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
A thing which makes no difference seems unlikely to exist [Le Poidevin]
10. Modality / A. Necessity / 3. Types of Necessity
Relevant necessity is always true for some situation (not all situations) [Beall/Restall]
14. Science / D. Explanation / 2. Types of Explanation / a. Types of explanation
In addition to causal explanations, they can also be inferential, or definitional, or purposive [Le Poidevin]
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
Judgement is always predicating a property of a subject [Beall/Restall]
19. Language / C. Assigning Meanings / 8. Possible Worlds Semantics
We can rest truth-conditions on situations, rather than on possible worlds [Beall/Restall]
19. Language / C. Assigning Meanings / 9. Indexical Semantics
We don't just describe a time as 'now' from a private viewpoint, but as a fact about the world [Le Poidevin]
19. Language / D. Propositions / 1. Propositions
Propositions commit to content, and not to any way of spelling it out [Beall/Restall]
26. Natural Theory / C. Causation / 1. Causation
The logical properties of causation are asymmetry, transitivity and irreflexivity [Le Poidevin]
27. Natural Reality / C. Space / 3. Points in Space
We can identify unoccupied points in space, so they must exist [Le Poidevin]
If spatial points exist, then they must be stationary, by definition [Le Poidevin]
27. Natural Reality / C. Space / 4. Substantival Space
Absolute space explains actual and potential positions, and geometrical truths [Le Poidevin]
27. Natural Reality / C. Space / 5. Relational Space
For relationists moving an object beyond the edge of space creates new space [Le Poidevin]
27. Natural Reality / C. Space / 6. Space-Time
We distinguish time from space, because it passes, and it has a unique present moment [Le Poidevin]
27. Natural Reality / D. Time / 1. Nature of Time / e. Eventless time
Since nothing occurs in a temporal vacuum, there is no way to measure its length [Le Poidevin]
Temporal vacuums would be unexperienced, unmeasured, and unending [Le Poidevin]
27. Natural Reality / D. Time / 2. Passage of Time / b. Rate of time
Time can't speed up or slow down, so it doesn't seem to be a 'process' [Le Poidevin]
27. Natural Reality / D. Time / 2. Passage of Time / f. Tenseless (B) series
To say that the past causes the present needs them both to be equally real [Le Poidevin]
The B-series doesn't seem to allow change [Le Poidevin]
If the B-universe is eternal, why am I trapped in a changing moment of it? [Le Poidevin]
27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow
An ordered series can be undirected, but time favours moving from earlier to later [Le Poidevin]
If time's arrow is causal, how can there be non-simultaneous events that are causally unconnected? [Le Poidevin]
If time's arrow is psychological then different minds can impose different orders on events [Le Poidevin]
There are Thermodynamic, Psychological and Causal arrows of time [Le Poidevin]
Presumably if time's arrow is thermodynamic then time ends when entropy is complete [Le Poidevin]
If time is thermodynamic then entropy is necessary - but the theory says it is probable [Le Poidevin]
Time's arrow is not causal if there is no temporal gap between cause and effect [Le Poidevin]
27. Natural Reality / D. Time / 2. Passage of Time / i. Time and motion
Instantaneous motion is an intrinsic disposition to be elsewhere [Le Poidevin]
The dynamic view of motion says it is primitive, and not reducible to objects, properties and times [Le Poidevin]
27. Natural Reality / D. Time / 2. Passage of Time / k. Temporal truths
If the present could have diverse pasts, then past truths can't have present truthmakers [Le Poidevin]
27. Natural Reality / D. Time / 3. Parts of Time / a. Beginning of time
The present is the past/future boundary, so the first moment of time was not present [Le Poidevin]
27. Natural Reality / D. Time / 3. Parts of Time / c. Intervals
The primitive parts of time are intervals, not instants [Le Poidevin]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
If time is infinitely divisible, then the present must be infinitely short [Le Poidevin]
27. Natural Reality / E. Cosmology / 10. Multiverse
The multiverse is distinct time-series, as well as spaces [Le Poidevin]
28. God / A. Divine Nature / 5. God and Time
How could a timeless God know what time it is? So could God be both timeless and omniscient? [Le Poidevin]