Combining Texts

All the ideas for 'The Case for Closure', 'Metaphysical Foundations of Natural Science' and 'In Praed.'

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6 ideas

9. Objects / B. Unity of Objects / 2. Substance / a. Substance
Substance is an intrinsic thing, so parts of substances can't also be intrinsic things [Duns Scotus]
     Full Idea: Substance ...is an ens per se. No part of a substance is an ens per se when it is part of a substance, because then it would be a particular thing, and one substance would be a particular thing from many things, which does not seem to be true.
     From: John Duns Scotus (In Praed. [1300], 15.1), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 26.1
     A reaction: The tricky bit is 'when it is a part of a substance', meaning a substance must cease to be a substance when it is subsumed into some greater substance. Maybe. Drops of water? Molecules? Bricks? Cells?
11. Knowledge Aims / B. Certain Knowledge / 2. Common Sense Certainty
Commitment to 'I have a hand' only makes sense in a context where it has been doubted [Hawthorne]
     Full Idea: If I utter 'I know I have a hand' then I can only be reckoned a cooperative conversant by my interlocutors on the assumption that there was a real question as to whether I have a hand.
     From: John Hawthorne (The Case for Closure [2005], 2)
     A reaction: This seems to point to the contextualist approach to global scepticism, which concerns whether we are setting the bar high or low for 'knowledge'.
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / c. Knowledge closure
How can we know the heavyweight implications of normal knowledge? Must we distort 'knowledge'? [Hawthorne]
     Full Idea: Those who deny skepticism but accept closure will have to explain how we know the various 'heavyweight' skeptical hypotheses to be false. Do we then twist the concept of knowledge to fit the twin desiderata of closue and anti-skepticism?
     From: John Hawthorne (The Case for Closure [2005], Intro)
     A reaction: [He is giving Dretske's view; Dretske says we do twist knowledge] Thus if I remember yesterday, that has the heavyweight implication that the past is real. Hawthorne nicely summarises why closure produces a philosophical problem.
We wouldn't know the logical implications of our knowledge if small risks added up to big risks [Hawthorne]
     Full Idea: Maybe one cannot know the logical consequences of the proposition that one knows, on account of the fact that small risks add up to big risks.
     From: John Hawthorne (The Case for Closure [2005], 1)
     A reaction: The idea of closure is that the new knowledge has the certainty of logic, and each step is accepted. An array of receding propositions can lose reliability, but that shouldn't apply to logic implications. Assuming monotonic logic, of course.
Denying closure is denying we know P when we know P and Q, which is absurd in simple cases [Hawthorne]
     Full Idea: How could we know that P and Q but not be in a position to know that P (as deniers of closure must say)? If my glass is full of wine, we know 'g is full of wine, and not full of non-wine'. How can we deny that we know it is not full of non-wine?
     From: John Hawthorne (The Case for Closure [2005], 2)
     A reaction: Hawthorne merely raises this doubt. Dretske is concerned with heavyweight implications, but how do you accept lightweight implications like this one, and then suddenly reject them when they become too heavy? [see p.49]
14. Science / D. Explanation / 2. Types of Explanation / j. Explanations by reduction
Science is the reduction of diverse forces and powers to a smaller number that explain them [Kant]
     Full Idea: All natural philosophy consists in the reduction of given forces apparently diverse to a smaller number of forces and powers sufficient for the explication of the actions of the former.
     From: Immanuel Kant (Metaphysical Foundations of Natural Science [1786], 534)
     A reaction: I'm beginning to think science is just tracking of complex forces and powers back to fundamental forces and powers. In which case, that is the analysis Kant is talking of. The standard model of physics would thrill him to bits.