9 ideas
14965 | Truth rests on Elimination ('A' is true → A) and Introduction (A → 'A' is true) [Gupta] |
Full Idea: The basic principles governing truth are Truth Elimination (sentence A follows from ''A' is true') and the converse Truth Introduction (''A' is true' follows from A), which combine into Tarski's T-schema - 'A' is true if and only if A. | |
From: Anil Gupta (Truth [2001], 5.1) | |
A reaction: Introduction and Elimination rules are the basic components of natural deduction systems, so 'true' now works in the same way as 'and', 'or' etc. This is the logician's route into truth. |
14968 | A weakened classical language can contain its own truth predicate [Gupta] |
Full Idea: If a classical language is expressively weakened - for example, by dispensing with negation - then it can contain its own truth predicate. | |
From: Anil Gupta (Truth [2001], 5.2) | |
A reaction: Thus the Tarskian requirement to move to a metalanguage for truth is only a requirement of a reasonably strong language. Gupta uses this to criticise theories that dispense with the metalanguage. |
14964 | The Liar reappears, even if one insists on propositions instead of sentences [Gupta] |
Full Idea: There is the idea that the Liar paradox is solved simply by noting that truth is a property of propositions (not of sentences), and the Liar sentence does not express a proposition. But we then say 'I am not now expressing a true proposition'! | |
From: Anil Gupta (Truth [2001], 5.1) | |
A reaction: Disappointed to learn this, since I think focusing on propositions (which are unambiguous) rather than sentences solves a huge number of philosophical problems. |
14969 | Strengthened Liar: either this sentence is neither-true-nor-false, or it is not true [Gupta] |
Full Idea: An example of the Strengthened Liar is the following statement SL: 'Either SL is neither-true-nor-false or it is not true'. This raises a serious problem for any theory that assesses the paradoxes to be neither true nor false. | |
From: Anil Gupta (Truth [2001], 5.4.2) | |
A reaction: If the sentence is either true or false it reduces to the ordinary Liar. If it is neither true nor false, then it is true. |
22076 | Being is only perceptible to itself as becoming [Schelling] |
Full Idea: Being is only perceptible to itself in the state of becoming. | |
From: Friedrich Schelling (Of Human Freedom [1809], p.403), quoted by Jean-François Courtine - Schelling p.90 | |
A reaction: Is the Enlightenment the era of Being, and the Romantic era that of Becoming? They like process, fluidity, even chaos. |
22074 | We must show that the whole of nature, because it is effective, is grounded in freedom [Schelling] |
Full Idea: What is required is to show that everything that is effective (nature, the world of things) is grounded in activity, life, freedom. | |
From: Friedrich Schelling (Of Human Freedom [1809], p.351), quoted by Jean-François Courtine - Schelling | |
A reaction: I take the ancestor of this view of nature to be the monads of Leibniz, as the active principle in nature. Because this is an idealist view, it starts with the absolute freedom of the Self, and presumably sees nature in its own image. |
22075 | Only idealism has given us the genuine concept of freedom [Schelling] |
Full Idea: Until the discovery of idealism, the genuine concept of freedom has been missing from every modern system, whether it be that of Leibniz or of Spinoza. | |
From: Friedrich Schelling (Of Human Freedom [1809], p.345), quoted by Jean-François Courtine - Schelling p.87 | |
A reaction: Spinoza denied free will, and Leibniz fudged it. Evidently more medieval theological accounts were not good enough. I presume Fichte is Schelling's hero, and he seems to see freedom as axiomatic about the Self. |
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. |