15 ideas
| 7493 | Let us reason together, saith the Lord [Isaiah] |
| Full Idea: Come now, and let us reason together, saith the Lord. | |
| From: Isaiah (23: Book of Isaiah [c.680 BCE], 01.18) | |
| A reaction: A verse which not only offers Biblical support for philosophy, but would also seem to be a challenge to Christian fideists. |
| 10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
| Full Idea: 'Equivocation' is when the terms do not mean the same thing in the premises and in the conclusion. | |
| From: JC Beall / G Restall (Logical Consequence [2005], Intro) |
| 10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall] |
| Full Idea: Logic is purely formal either when it is invariant under permutation of object (Tarski), or when it has totally abstracted away from all contents, or it is the constitutive norms for thought. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) | |
| A reaction: [compressed] The third account sounds rather woolly, and the second one sounds like a tricky operation, but the first one sounds clear and decisive, so I vote for Tarski. |
| 10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
| Full Idea: Technical work on logical consequence has either focused on proofs, where validity is the existence of a proof of the conclusions from the premises, or on models, which focus on the absence of counterexamples. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
| Full Idea: Two different views of logical consequence are necessary truth-preservation (based on modelling possible worlds; favoured by Realists), or truth-preservation based on the meanings of the logical vocabulary (differing in various models; for Anti-Realists). | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) | |
| A reaction: Thus Dummett prefers the second view, because the law of excluded middle is optional. My instincts are with the first one. |
| 10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
| Full Idea: A logical step is a 'material consequence' and not a formal one, if we need the contents as well as the structure or form. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 2) |
| 10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
| Full Idea: If a conclusion follows from an empty collection of premises, it is true by logic alone, and is a 'logical truth' (sometimes a 'tautology'), or, in the proof-centred approach, 'theorems'. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 4) | |
| A reaction: These truths are written as following from the empty set Φ. They are just implications derived from the axioms and the rules. |
| 10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
| Full Idea: Models are abstract mathematical structures that provide possible interpretations for each of the non-logical primitives in a formal language. | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
| Full Idea: There are many proof-systems, the main being Hilbert proofs (with simple rules and complex axioms), or natural deduction systems (with few axioms and many rules, and the rules constitute the meaning of the connectives). | |
| From: JC Beall / G Restall (Logical Consequence [2005], 3) |
| 22265 | I can't defend the view that the majority values of a community are thereby right [Sandel] |
| Full Idea: Insofar as 'communitarian' is another name for majoritarianism, or for the idea that rights should rest on the values that predominate in any given community at any given time, it is not a view I would defend. | |
| From: Michael J. Sandel (The Limits of Communitarianism [1998], 'Where') | |
| A reaction: I should hope not. You could soon end up as a good nazi if you follow that route. Sandel defends a critical view of community values (implying a role for philosophy?). The community good must be continually negotiated. Sounds fine to me. |
| 22268 | If persons define themselves by a group membership, insults to that group are a real harm [Sandel] |
| Full Idea: For persons who understand themselves as defined by the ethnic or religious group to which they belong, an insult to the group can inflict a harm as real and as damaging as some physical harms. | |
| From: Michael J. Sandel (The Limits of Communitarianism [1998], 'Free speech') | |
| A reaction: In Britain many people fully define themselves by their allegiance to a football club. Really! They usually learn to laugh off an insult to their club, but it hurts. Laughing off an insult is an essential modern skill - up to a point. |
| 22267 | In the liberal view an insult to my group doesn't hurt me, since I'm defined by choices not groups [Sandel] |
| Full Idea: By the liberal conception of a person, my dignity could never be damaged by an insult to a group with which I identify, because what matters is not my social role, but my capacity to choose that role. | |
| From: Michael J. Sandel (The Limits of Communitarianism [1998], 'Free speech') | |
| A reaction: If I'm defined by my capacity to choose, and I choose to join some group, why is an insult to that group not an insult to my capacity to choose? How do you insult a liberal? 'I despise your individual freedom!'. |
| 22266 | The case for religious liberty depends on the religion contributing to a morally good life [Sandel] |
| Full Idea: Unless there were reason to believe that religious beliefs and practices contribute to morally admirable ways of life, the case for a right to religious liberty would be weakened. | |
| From: Michael J. Sandel (The Limits of Communitarianism [1998], 'Religious') | |
| A reaction: I think many religious people would deny that their religion is primarily moral. (W.Blake: 'If morality is Christianity, then Socrates was the saviour'). Whose concept of a morally good life is Sandel referring to? |
| 7608 | The world is established, and cannot be moved [Isaiah] |
| Full Idea: The world is also established, that it cannot be moved. | |
| From: Isaiah (23: Book of Isaiah [c.680 BCE], 93.1) | |
| A reaction: This verse caused big trouble for Galileo. The only reason I can think of for Isaiah to write this is that occasionally people were prone to panic, and worry that the Earth might suddenly and abruptly be moved. |
| 7343 | Beside me there is no God [Isaiah] |
| Full Idea: I am the first, and I am the last; and beside me there is no God. | |
| From: Isaiah (23: Book of Isaiah [c.680 BCE], 44.06) | |
| A reaction: This seems to be the first clear statement (c. 680 BCE) of monotheism, certainly preceding any Greek views on the subject (cf. Idea 2629,Idea 7347). It is not just an arrogant assertion by the jews, but a humble sacrifice, donating their god to humanity. |