6408
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Russell needed three extra axioms to reduce maths to logic: infinity, choice and reducibility [Grayling]
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Full Idea:
In order to deduce the theorems of mathematics from purely logical axioms, Russell had to add three new axioms to those of standards logic, which were: the axiom of infinity, the axiom of choice, and the axiom of reducibility.
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From:
A.C. Grayling (Russell [1996], Ch.2)
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A reaction:
The third one was adopted to avoid his 'barber' paradox, but many thinkers do not accept it. The interesting question is why anyone would 'accept' or 'reject' an axiom.
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16648
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Accidents must have formal being, if they are principles of real action, and of mental action and thought [Duns Scotus]
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Full Idea:
Accidents are principles of acting and principles of cognizing substance, and are the per se objects of the senses. But it is ridiculous to say that something is a principle of acting (either real or intentional) and yet does not have any formal being.
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From:
John Duns Scotus (Ordinatio [1302], IV.12.1), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 10.5
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A reaction:
Pasnau cites this as the key scholastic argument for accidental properties having some independent and real existence (as required for Transubstantiation). Rival views say accidents are just 'modes' of a thing's existence. Aquinas compromised.
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15386
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If only the singular exists, science is impossible, as that relies on true generalities [Duns Scotus, by Panaccio]
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Full Idea:
Scotus argued that if everything is singular, with no objective common feature, science would be impossible, as it proceeds from general concepts. General is the opposite of singular, so it would be inadequate to understand a singular reality.
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From:
report of John Duns Scotus (Ordinatio [1302]) by Claude Panaccio - Medieval Problem of Universals 'John Duns'
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A reaction:
[compressed] It is a fact that if you generalise about 'tigers', you are glossing over the individuality of each singular tiger. That is OK for 'electron', if they really are identical, but our general predicates may be imposing identity on electrons.
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16632
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We distinguish one thing from another by contradiction, because this is, and that is not [Duns Scotus]
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Full Idea:
What is it [that establishes distinctness of things]? It is, to be sure, that which is universally the reason for distinguishing one thing from another: namely, a contradiction…..If this is, and that is not, then they are not the same entity in being.
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From:
John Duns Scotus (Ordinatio [1302], IV.11.3), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 08.2
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A reaction:
This is a remarkably intellectualist view of such things. John Wycliff, apparently, enquired about how animals were going to manage all this sort of thing. It should appeal to the modern logical approach to metaphysics.
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13094
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The haecceity is the featureless thing which gives ultimate individuality to a substance [Duns Scotus, by Cover/O'Leary-Hawthorne]
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Full Idea:
For Scotus, the haecceity of an individual was a positive non-quidditative entity which, together with a common nature from which it was formally distinct, played the role of the ultimate differentia, thus individuating the substance.
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From:
report of John Duns Scotus (Ordinatio [1302]) by Cover,J/O'Leary-Hawthorne,J - Substance and Individuation in Leibniz 6.1.3
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A reaction:
Most thinkers seem to agree (with me) that this is a non-starter, an implausible postulate designed to fill a gap in a metaphysic that hasn't been properly worked out. Leibniz is the hero who faces the problem and works around it.
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16770
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It is absurd that there is no difference between a genuinely unified thing, and a mere aggregate [Duns Scotus]
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Full Idea:
It seems absurd …that there should be no difference between a whole that is one thing per se, and a whole that is one thing by aggregation, like a cloud or a heap.
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From:
John Duns Scotus (Ordinatio [1302], III.2.2), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 25.5
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A reaction:
Leibniz invented monads because he was driven crazy by the quest for 'true unity' in things. Objective unity may be bogus, but I suspect that imposing plausible unity on things is the only way we can grasp the world.
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12699
|
A body would be endless disunited parts, if it did not have a unifying form or soul [Leibniz]
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Full Idea:
Without soul or form of some kind, a body would have no being, because no part of it can be designated which does not in turn consist of more parts. Thus nothing could be designated in a body which could be called 'this thing', or a unity.
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From:
Gottfried Leibniz (Conspectus libelli (book outline) [1678], A6.4.1988), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 1
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A reaction:
The locution 'soul or form' is disconcerting, and you have to spend some time with Leibniz to get the hang of it. The 'soul' is not intelligent, and is more like a source of action and response.
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12700
|
Form or soul gives unity and duration; matter gives multiplicity and change [Leibniz]
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Full Idea:
Substantial form, or soul, is the principle of unity and duration, matter is that of multiplicity and change
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From:
Gottfried Leibniz (Conspectus libelli (book outline) [1678], A6.4.1398-9), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 2
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A reaction:
Leibniz was a fan of the unfashionable Aristotle, and tried to put a spin on his views consonant with contemporary Hobbesian mechanistic views. Oddly, he likes the idea that 'form' is indestructable, which I don't understand.
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12736
|
If we understand God and his choices, we have a priori knowledge of contingent truths [Leibniz, by Garber]
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Full Idea:
Insofar as we have some insight into how God chooses, we can know a priori the laws of nature that God chooses for this best of all possible worlds. In this way, it is possible to have genuine a priori knowledge of contingent truths.
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From:
report of Gottfried Leibniz (Conspectus libelli (book outline) [1678], A6.4.1998-9) by Daniel Garber - Leibniz:Body,Substance,Monad 6
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A reaction:
I think it would be doubtful whether our knowledge of God's choosings would count as a priori. How do we discover them? Ah! We derive God from the ontological argument, and his choosings from the divine perfection implied thereby.
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