Ideas from 'Logical Pluralism' by JC Beall / G Restall [2006], by Theme Structure
[found in 'Logical Pluralism' by Beall,J/Restall,G [OUP 2006,9780199288410]].
Click on the Idea Number for the full details 
back to texts

expand these ideas
3. Truth / A. Truth Problems / 1. Truth
13252

Some truths have true negations

3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
13247

A truthmaker is an object which entails a sentence

4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
13249

(∀x)(A v B)  (∀x)A v (∃x)B) is valid in classical logic but invalid intuitionistically

4. Formal Logic / E. Nonclassical Logics / 5. Relevant Logic
13255

Relevant logic may reject transitivity

13243

Excluded middle must be true for some situation, not for all situations

13242

It's 'relevantly' valid if all those situations make it true

13246

Relevant logic does not abandon classical logic

13245

Relevant consequence says invalidity is the conclusion not being 'in' the premises

13254

A doesn't imply A  that would be circular

4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
13250

Free logic terms aren't existential; classical is nonempty, with referring names

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
13235

Logic studies consequence; logical truths are consequences of everything, or nothing

13238

Syllogisms are only logic when they use variables, and not concrete terms

5. Theory of Logic / A. Overview of Logic / 2. History of Logic
13234

The view of logic as knowing a body of truths looks outofdate

5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
13232

Logic studies arguments, not formal languages; this involves interpretations

5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
13241

The model theory of classical predicate logic is mathematics

5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
13253

There are several different consequence relations

5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence =
13240

A sentence follows from others if they always model it

5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
13236

Logical truth is much more important if mathematics rests on it, as logicism claims

5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / d. The Preface paradox
13237

Preface Paradox affirms and denies the conjunction of propositions in the book

10. Modality / A. Necessity / 3. Types of Necessity
13244

Relevant necessity is always true for some situation (not all situations)

18. Thought / A. Modes of Thought / 1. Thought
13239

Judgement is always predicating a property of a subject

19. Language / C. Semantics / 5. Possible Worlds Semantics
13248

We can rest truthconditions on situations, rather than on possible worlds

19. Language / E. Propositions / 1. Propositions
13233

Propositions commit to content, and not to any way of spelling it out
