Combining Philosophers

All the ideas for Nicolas Malebranche, M.R. Ayers and Gerhard Gentzen

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


24 ideas

5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna]
The logical connectives are 'defined' by their introduction rules [Gentzen]
Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
Natural deduction shows the heart of reasoning (and sequent calculus is just a tool) [Gentzen, by Hacking]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / d. Counting via concepts
Counting 'coin in this box' may have coin as the unit, with 'in this box' merely as the scope [Ayers]
If counting needs a sortal, what of things which fall under two sortals? [Ayers]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave]
7. Existence / B. Change in Existence / 4. Events / a. Nature of events
Events do not have natural boundaries, and we have to set them [Ayers]
8. Modes of Existence / B. Properties / 8. Properties as Modes
Everything that exists is either a being, or some mode of a being [Malebranche]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
To express borderline cases of objects, you need the concept of an 'object' [Ayers]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
Speakers need the very general category of a thing, if they are to think about it [Ayers]
We use sortals to classify physical objects by the nature and origin of their unity [Ayers]
Seeing caterpillar and moth as the same needs continuity, not identity of sortal concepts [Ayers]
Recognising continuity is separate from sortals, and must precede their use [Ayers]
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
Could the same matter have more than one form or principle of unity? [Ayers]
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
If there are two objects, then 'that marble, man-shaped object' is ambiguous [Ayers]
9. Objects / D. Essence of Objects / 5. Essence as Kind
Sortals basically apply to individuals [Ayers]
9. Objects / E. Objects over Time / 5. Temporal Parts
You can't have the concept of a 'stage' if you lack the concept of an object [Ayers]
Temporal 'parts' cannot be separated or rearranged [Ayers]
9. Objects / F. Identity among Objects / 1. Concept of Identity
Some say a 'covering concept' completes identity; others place the concept in the reference [Ayers]
9. Objects / F. Identity among Objects / 3. Relative Identity
If diachronic identities need covering concepts, why not synchronic identities too? [Ayers]
26. Natural Theory / C. Causation / 9. General Causation / d. Causal necessity
In a true cause we see a necessary connection [Malebranche]
A true cause must involve a necessary connection between cause and effect [Malebranche]