Combining Texts

All the ideas for 'fragments/reports', 'Presentism and Properties' and 'Counterfactuals'

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6 ideas

10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Lewis says indicative conditionals are truth-functional [Lewis, by Jackson]
     Full Idea: Unlike Stalnaker, Lewis holds that indicative conditionals have the truth conditions of material conditionals.
     From: report of David Lewis (Counterfactuals [1973]) by Frank Jackson - Conditionals 'Further'
     A reaction: Thus Lewis only uses the possible worlds account for subjunctive conditionals, where Stalnaker uses it for both. Lewis is defending the truth-functional account for the indicative conditionals.
10. Modality / B. Possibility / 9. Counterfactuals
In good counterfactuals the consequent holds in world like ours except that the antecedent is true [Lewis, by Horwich]
     Full Idea: According to Lewis, a counterfactual holds when the consequent is true in possible worlds very like our own except for the fact that the antecedent is true.
     From: report of David Lewis (Counterfactuals [1973]) by Paul Horwich - Lewis's Programme p.213
     A reaction: Presumably the world being very like our own would make it unlikely that there would be anything else to cause the consequent, apart from the counterfactual antecedent.
25. Social Practice / E. Policies / 5. Education / b. Education principles
Learned men gain more in one day than others do in a lifetime [Posidonius]
     Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes.
     From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078
     A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book.
26. Natural Theory / D. Laws of Nature / 4. Regularities / b. Best system theory
A law of nature is a general axiom of the deductive system that is best for simplicity and strength [Lewis]
     Full Idea: A contingent generalization is a law of nature if and only if it appears as a theorem (or axiom) in each of the true deductive systems that achieves a best combination of simplicity and strength.
     From: David Lewis (Counterfactuals [1973], 3.3)
27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure
Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]
     Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness.
     From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42
     A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them.
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
I am a presentist, and all language and common sense supports my view [Bigelow]
     Full Idea: I am a presentist: nothing exists which is not present. Everyone believed this until the nineteenth century; it is writing into the grammar of natural languages; it is still assumed in everyday life, even by philosophers who deny it.
     From: John Bigelow (Presentism and Properties [1996], p.36), quoted by Trenton Merricks - Truth and Ontology
     A reaction: The most likely deniers of presentism seem to be physicists and cosmologists who have overdosed on Einstein. On the whole I vote for presentism, but what justifies truths about the past and future. Traces existing in the present?