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All the ideas for 'Leibniz: Guide for the Perplexed', 'On the General Idea of Proof Theory' and 'fragments/reports'

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7 ideas

5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Logical consequence isn't a black box (Tarski's approach); we should explain how arguments work [Prawitz]
     Full Idea: Defining logical consequence in the way Tarski does is a rather meagre result, treating an argument as a black box, observing input and output, while disregarding inner structure. We should define logical consequence on the basis of valid arguments.
     From: Dag Prawitz (On the General Idea of Proof Theory [1974], §2)
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Model theory looks at valid sentences and consequence, but not how we know these things [Prawitz]
     Full Idea: In model theory, which has dominated the last decades, one concentrates on logically valid sentences, and what follows logically from what, but one disregards questions concerning how we know these things.
     From: Dag Prawitz (On the General Idea of Proof Theory [1974], §1)
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
Substance needs independence, unity, and stability (for individuation); also it is a subject, for predicates [Perkins]
     Full Idea: For individuation, substance needs three properties: independence, to separate it from other things; unity, to call it one thing, rather than an aggregate; and permanence or stability over time. Its other role is as subject for predicates.
     From: Franklin Perkins (Leibniz: Guide for the Perplexed [2007], 3.1)
     A reaction: Perkins is describing the Aristotelian view, which is taken up by Leibniz. 'Substance' is not a controversial idea, if we see that it only means that the world is full of 'things'. It is an unusual philosopher wholly totally denies that.
23. Ethics / C. Virtue Theory / 1. Virtue Theory / a. Nature of virtue
We must choose in which of the virtues we wish to excel [Panaetius]
     Full Idea: Humans have four roles in life, of which the fourth involves choices, of career, and of the virtue in which one wishes to excel.
     From: Panaetius (fragments/reports [c.145 BCE]), quoted by Elizabeth Asmis - Panaetius
     A reaction: Panaetius strikes me as exceptionally wise. A big gap in Aristotle is the fact that we cannot excel in all virtues, and that therefore some choice is required. By what criteria? We have the Gauguin problem (excel in one, disgraceful in the others).
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / b. Living naturally
Panaetius said we should live according to our natural starting-points [Panaetius, by Asmis]
     Full Idea: Panaetius reformulated the Stoic goal as living in accordance with the starting-points given to us by nature.
     From: report of Panaetius (fragments/reports [c.145 BCE]) by Elizabeth Asmis - Panaetius
     A reaction: This sounds remarkably like the substitution of meritocratic equality of opportunity for communistic actual equality. In other words, it doesn't sound very Stoic. 'Live according to nature' implies more restraint than this ambitious version.
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Panaetius identified courage with great-mindedness, preferring civic courage to military [Panaetius, by Asmis]
     Full Idea: Panaetius recast the virtue of courage as 'greatmindedness' (Aristotle's paramount virtue), he demoted military valour and gave priority to courage displayed in civic life.
     From: report of Panaetius (fragments/reports [c.145 BCE]) by Elizabeth Asmis - Panaetius
     A reaction: I find this very appealing, as I am increasingly horrified by our denigration of the people who implement our democracy for us. We urgently need to get back to the Greek idea of civic virtue, and this idea of Panaetius should be widely promulgated.
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Souls are born, since they are sensitive and inherited, so they must perish [Panaetius, by Cicero]
     Full Idea: Panaetius says that whatever is born must perish, and souls are clearly born, as shown by the resemblance of children to their parents in disposition as well as body; also, anything sensible of pain is susceptible to sickness, and hence perishes.
     From: report of Panaetius (fragments/reports [c.145 BCE]) by M. Tullius Cicero - Tusculan Disputations I.xxxii
     A reaction: These seem to be rather good arguments. If we actually observe what someone's soul is like (through character) it seems rooted in a family and culture, and it certainly seems susceptible to disease. An empirical approach.