14 ideas
| 5035 | The two basics of reasoning are contradiction and sufficient reason [Leibniz] |
| Full Idea: The two first principles of reasoning are: the principle of contradiction, and the principle of the need for giving a reason. | |
| From: Gottfried Leibniz (A Specimen of Discoveries [1686], p.75) | |
| A reaction: Could animals have any reasoning ability (say, in solving a physical problem)? Leibniz's criteria both require language. Note the overlapping of the principle of sufficient reason (there IS a reason) with the contractual idea of GIVING reasons. |
| 23291 | Without truth, both language and thought are impossible [Davidson] |
| Full Idea: Without a grasp of the concept of truth, not only language, but thought itself, is impossible. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.16) | |
| A reaction: Davidson never mentions animals, but I like this idea because it points to importance of truth for animals as well. I say that truth is relevant to any mind that makes judgements - and quite small animals (e.g. ants and spiders) make judgements. |
| 23284 | Plato's Forms confused truth with the most eminent truths, so only Truth itself is completely true [Davidson] |
| Full Idea: Plato's conflation of abstract universals with entities of supreme value reinforced the confusion of truth with the most eminent truths. …The only perfect exemplar of a Form is the Form itself, …and only truth itself is completely true. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.3) | |
| A reaction: Even non-subscribers to Plato often talk as if there were some grand thing called the Truth with a capital T, quite often used in a religious context. Truth is the hallmark of successful (non-fanciful) thought. |
| 23286 | Truth can't be a goal, because we can neither recognise it nor confim it [Davidson] |
| Full Idea: Since it is neither visible as a target, nor recognisable when achieved, there is no point in calling truth a goal. We should only aim at increasing confidence in our beliefs, by collecting further evidence or checking our calculations. | |
| From: Donald Davidson (Truth Rehabilitated [1997], P.6) | |
| A reaction: This is mainly aimed at pragmatists, but Davidson obviously subscribes (as do I) to their fallibilist view of knowledge. |
| 23292 | Correspondence can't be defined, but it shows how truth depends on the world [Davidson] |
| Full Idea: Correspondence, while it is empty as a definition, does capture the thought that truth depends on how the world is. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.16) | |
| A reaction: Just don't try to give a precise account of the correspondence between two things (thoughts and facts) which are so utterly different in character. |
| 23288 | When Tarski defines truth for different languages, how do we know it is a single concept? [Davidson] |
| Full Idea: We have to wonder how we know that it is some single concept which Tarski indicates how to define for each of a number of well-behaved languages. | |
| From: Donald Davidson (Truth Rehabilitated [1997], P.11) | |
| A reaction: Davidson says that Tarski makes the assumption that it is a single concept, but fails to demonstrate the fact. This resembles Frege's Julius Caesar problem - of how you know whether your number definition has defined a number. |
| 23287 | Disquotation only accounts for truth if the metalanguage contains the object language [Davidson] |
| Full Idea: Disquotation cannot pretend to give a complete account of the concept of truth, since it works only in the special case where the metalanguage contains the object language. Neither can contain their own truth predicate. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.10) | |
| A reaction: Presumably more sophisticated and complete accounts would need a further account of translation between languages - which explains Quine's interest in that topic. […see this essay, p.12] |
| 23285 | If we try to identify facts precisely, they all melt into one (as the Slingshot Argument proves) [Davidson] |
| Full Idea: If we try to provide a serious semantics for reference to facts, we discover that they melt into one; there is no telling them apart. The relevant argument (the 'Slingshot') was credited to Frege by Alonso Church. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.5) | |
| A reaction: This sounds like good grounds for not attempting to be too precise. 'There are bluebells in my local wood' identifies a fact by words, but even an animal can distinguish this fact. Only a logician dreams of making its content precise. |
| 5038 | Assume that mind and body follow their own laws, but God has harmonised them [Leibniz] |
| Full Idea: Why not assume that God initially created the soul and body with so much ingenuity that, whilst each follows its own laws and properties and operations, all thing agree most beautifull among themselves? This is the 'hypothesis of concomitance'. | |
| From: Gottfried Leibniz (A Specimen of Discoveries [1686], p.80) | |
| A reaction: They may be in beautifully planned harmony, but how do we know that they are in harmony? Presumably their actions must be compared, and God would even have to harmonise the comparison. Parallelism seems to imply epiphenomenalism or idealism. |
| 23289 | Knowing the potential truth conditions of a sentence is necessary and sufficient for understanding [Davidson] |
| Full Idea: It is clear that someone who knows under what conditions a sentence would be true understands that sentence, …and if someone does not know under what conditions it would be true then they do not understand it. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.13) | |
| A reaction: I've always subscribed to this view. Langauge is meaningless if you can't relate it to reality, and I don't think there could be a language without an intuitive notion of truth. |
| 23290 | It could be that the use of a sentence is explained by its truth conditions [Davidson] |
| Full Idea: It may be that sentences are used as they are because of their truth conditions, and they have the truth conditions they do because of how they are used. | |
| From: Donald Davidson (Truth Rehabilitated [1997], p.13) | |
| A reaction: I've always taken the attempt to explain meaning by use as absurd. It is similar to trying to explain mind in terms of function. In each case, what is the intrinsic nature of the thing, which makes that use or that function possible? |
| 16713 | Philosophers are the forefathers of heretics [Tertullian] |
| Full Idea: Philosophers are the forefathers of heretics. | |
| From: Tertullian (works [c.200]), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 20.2 |
| 6610 | I believe because it is absurd [Tertullian] |
| Full Idea: I believe because it is absurd ('Credo quia absurdum est'). | |
| From: Tertullian (works [c.200]), quoted by Robert Fogelin - Walking the Tightrope of Reason n4.2 | |
| A reaction: This seems to be a rather desperate remark, in response to what must have been rather good hostile arguments. No one would abandon the support of reason if it was easy to acquire. You can't deny its engaging romantic defiance, though. |
| 5037 | God doesn't decide that Adam will sin, but that sinful Adam's existence is to be preferred [Leibniz] |
| Full Idea: God does not decide whether Adam should sin, but whether that series of things in which there is an Adam whose perfect individual notion involves sin should nevertheless be preferred to others. | |
| From: Gottfried Leibniz (A Specimen of Discoveries [1686], p.78) | |
| A reaction: Compare whether the person responsible for setting a road speed limit is responsible for subsequent accidents. Leibniz's belief that the world could have been made no better than it is (by an omnipotent being) strikes me as blind faith, not an argument. |