9 ideas
| 18812 | Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt] |
| Full Idea: Tarski made a division of logical and non-logical vocabulary. He then defined a model as a non-logical assignment satisfying the corresponding sentential function. Then a conclusion follows logically if every model of the premises models the conclusion. | |
| From: report of Alfred Tarski (The Concept of Logical Consequence [1936]) by Ian Rumfitt - The Boundary Stones of Thought 3.2 | |
| A reaction: [compressed] This is Tarski's account of logical consequence, which follows on from his account of truth. 'Logical validity' is then 'true in every model'. Rumfitt doubts whether Tarski has given the meaning of 'logical consequence'. |
| 13344 | X follows from sentences K iff every model of K also models X [Tarski] |
| Full Idea: The sentence X follows logically from the sentences of the class K if and only if every model of the class K is also a model of the sentence X. | |
| From: Alfred Tarski (The Concept of Logical Consequence [1936], p.417) | |
| A reaction: [see Idea 13343 for his account of a 'model'] He is offering to define logical consequence in general, but this definition fits what we now call 'semantic consequence', written |=. This it is standard practice to read |= as 'models'. |
| 13343 | A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski] |
| Full Idea: An arbitrary sequence of objects which satisfies every sentential function of the sentences L' will be called a 'model' or realization of the class L of sentences. There can also be a model of a single sentence is this way. | |
| From: Alfred Tarski (The Concept of Logical Consequence [1936], p.417) | |
| A reaction: [L' is L with the constants replaced by variables] Tarski is the originator of model theory, which is central to modern logic. The word 'realization' is a helpful indicator of what he has in mind. A model begins to look like a possible world. |
| 13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
| Full Idea: A class of sentences can be called 'analytical' if every sequence of objects is a model of it. | |
| From: Alfred Tarski (The Concept of Logical Consequence [1936], p.418) | |
| A reaction: See Idea 13344 and Idea 13343 for the context of this assertion. |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| Full Idea: The six perfections are of giving, morality, patience, vigour, meditation, and wisdom. | |
| From: Nagarjuna (Mahaprajnaparamitashastra [c.120], 88) | |
| A reaction: What is 'morality', if giving is not part of it? I like patience and vigour being two of the virtues, which immediately implies an Aristotelian mean (which is always what is 'appropriate'). |
| 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? |