Combining Texts

All the ideas for 'Conditionals', 'On the Freedom of the Will' and 'On Sufficient Reason'

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7 ideas

2. Reason / B. Laws of Thought / 1. Laws of Thought
Necessities rest on contradiction, and contingencies on sufficient reason [Leibniz]
     Full Idea: The principle of contradiction is the principle of necessity, and the principle that a sufficient reason must be given is the principle of contingency.
     From: Gottfried Leibniz (On Sufficient Reason [1686], p.95)
     A reaction: [this paragraph is actually undated] Contradictions occur in concrete actuality, as well as in theories and formal systems. If so, then there are necessities in nature. Are they discoverable a posteriori? Leibniz says not.
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington]
     Full Idea: If your interest in logic is confined to applications to mathematics or other a priori matters, it is fine for validity to preserve certainty, ..but if you use conditionals when arguing about contingent matters, then great caution will be required.
     From: Dorothy Edgington (Conditionals [2001], 17.2.1)
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
There are many different conditional mental states, and different conditional speech acts [Edgington]
     Full Idea: As well as conditional beliefs, there are conditional desires, hopes, fears etc. As well as conditional statements, there are conditional commands, questions, offers, promises, bets etc.
     From: Dorothy Edgington (Conditionals [2001], 17.3.4)
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington]
     Full Idea: Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? Are they non-truth-functional, like 'because' or 'before'? Do the values of A and B, in some cases, leave open the value of 'If A,B'?
     From: Dorothy Edgington (Conditionals [2001], 17.1)
     A reaction: I would say they are not truth-functional, because the 'if' asserts some further dependency relation that goes beyond the truth or falsity of A and B. Logical ifs, causal ifs, psychological ifs... The material conditional ⊃ is truth-functional.
'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington]
     Full Idea: If it were possible to have A true, B false, and If A,B true, it would be unsafe to infer B from A and If A,B: modus ponens would thus be invalid. Hence 'If A,B' must entail ¬(A & ¬B).
     From: Dorothy Edgington (Conditionals [2001], 17.1)
     A reaction: This is a firm defence of part of the truth-functional view of conditionals, and seems unassailable. The other parts of the truth table are open to question, though, if A is false, or they are both true.
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / g. Moral responsibility
We clearly feel responsible for our deeds, because we are quite certain that we did them [Schopenhauer]
     Full Idea: Another fact of consciousness ...is the wholly clear and certain feeling of responsibility for what we do, of the accountability of our actions, which rests on the unshakable certainty that we ourselves are the doers of our deeds.
     From: Arthur Schopenhauer (On the Freedom of the Will [1841], p.93-4), quoted by Christopher Janaway - Schopenhauer 7 'Freedom'
     A reaction: The point is that we have this feeling even if we do not believe in free will. I am struck by the fact that responsibility is very obvious in our own case, even if it is not when we objectively consider other people. Even villains can feel guilty.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / c. Essence and laws
Each of the infinite possible worlds has its own laws, and the individuals contain those laws [Leibniz]
     Full Idea: As there are an infinity of possible worlds, there are also an infinity of laws, some proper to one, another to another, and each possible individual of any world contains in its own notion the laws of its world.
     From: Gottfried Leibniz (On Sufficient Reason [1686], p.95)
     A reaction: Hence Leibniz is not really a scientific essentialist, in that he doesn't think the laws arise out of the nature of the matter consituting the world. I wonder if the primitive matter of bodies which attaches to the monads is the same in each world?