Combining Texts

All the ideas for 'Summa totius logicae', 'Ignorance: a Case for Scepticism' and 'Gentzen's Analysis of First-Order Proofs'

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15 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 / A. Overview of Logic / 1. Overview of Logic
Logic is based on transitions between sentences [Prawitz]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
Natural deduction introduction rules may represent 'definitions' of logical connectives [Prawitz]
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 / H. Proof Systems / 4. Natural Deduction
In natural deduction, inferences are atomic steps involving just one logical constant [Prawitz]
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]
13. Knowledge Criteria / C. External Justification / 6. Contextual Justification / b. Invariantism
The meaning of 'know' does not change from courtroom to living room [Unger]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
No one knows anything, and no one is ever justified or reasonable [Unger]
13. Knowledge Criteria / D. Scepticism / 4. Demon Scepticism
An evil scientist may give you a momentary life, with totally false memories [Unger]
19. Language / D. Propositions / 4. Mental Propositions
Some concepts for propositions exist only in the mind, and in no language [William of Ockham]