14018
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Is Sufficient Reason self-refuting (no reason to accept it!), or is it a legitimate explanatory tool? [Bourne]
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Full Idea:
Mackie (1983) dismisses the Principle of Sufficient Reason quickly, arguing that it is self-refuting: there is no sufficient reason to accept it. However, a principle is not invalidated by not applying to itself; it can be a powerful heuristic tool.
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From:
Craig Bourne (A Future for Presentism [2006], 6.VI)
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A reaction:
If God was entirely rational, and created everything, that would be a sufficient reason to accept the principle. You would never, though, get to the reason why God was entirely rational. Something will always elude the principle.
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13342
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Carnap defined consequence by contradiction, but this is unintuitive and changes with substitution [Tarski on Carnap]
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Full Idea:
Carnap proposed to define consequence as 'sentence X follows from the sentences K iff the sentences K and the negation of X are contradictory', but 1) this is intuitively impossible, and 2) consequence would be changed by substituting objects.
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From:
comment on Rudolph Carnap (The Logical Syntax of Language [1934], p.88-) by Alfred Tarski - The Concept of Logical Consequence p.414
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A reaction:
This seems to be the first step in the ongoing explicit discussion of the nature of logical consequence, which is now seen by many as the central concept of logic. Tarski brings his new tool of 'satisfaction' to bear.
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13251
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Each person is free to build their own logic, just by specifying a syntax [Carnap]
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Full Idea:
In logic, there are no morals. Everyone is at liberty to build his own logic, i.e. his own form of language. All that is required is that he must state his methods clearly, and give syntactical rules instead of philosophical arguments.
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From:
Rudolph Carnap (The Logical Syntax of Language [1934], §17), quoted by JC Beall / G Restall - Logical Pluralism 7.3
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A reaction:
This is understandable, but strikes me as close to daft relativism. If I specify a silly logic, I presume its silliness will be obvious. By what criteria? I say the world dictates the true logic, but this is a minority view.
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4761
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The 'error theory' of morals says there is no moral knowledge, because there are no moral facts [Mackie, by Engel]
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Full Idea:
Mackie's 'error theory' of ethics says that if a fact is something that corresponds to a true proposition, there are actually no moral facts, hence no knowledge of what moral statements are about.
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From:
report of J.L. Mackie (Ethics: Inventing Right and Wrong [1977]) by Pascal Engel - Truth §4.2
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A reaction:
Personally I am inclined to think that there are moral facts (about what nature shows us constitutes a good human being), based on virtue theory. Mackie is a good warning, though, against making excessive claims. You end up like a bad scientist.
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14019
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Relativity denies simultaneity, so it needs past, present and future (unlike Presentism) [Bourne]
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Full Idea:
Special Relativity denies absolute simultaneity, and therefore requires a past and a future, as well as a present. The Presentist, however, only requires the present.
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From:
Craig Bourne (A Future for Presentism [2006], 6.VII)
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A reaction:
It is nice to accuse Relativity of ontological extravagence. When it 'requires' past and future, that may not be a massive commitment, since the whole theory is fairly operationalist, according to Putnam.
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14003
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Time is tensed or tenseless; the latter says all times and objects are real, and there is no passage of time [Bourne]
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Full Idea:
Theories of time are in two broad categories, the tenseless and the tensed theories. In tenseless theories, all times are equally real, as are all objects located at them, and there is no passage of time from future to present to past. It's the B-series.
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From:
Craig Bourne (A Future for Presentism [2006], Intro IIa)
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A reaction:
It might solve a few of the problems, but is highly counterintuitive. Presumably it makes the passage of time an illusion, and gives no account of how events 'happen', or of their direction, and it leaves causation out on a limb. I'm afraid not.
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14005
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B-series objects relate to each other; A-series objects relate to the present [Bourne]
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Full Idea:
Objects in the B-series are earlier than, later than, or simultaneous with each other, whereas objects in the A-series are earlier than, later than or simultaneous with the present.
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From:
Craig Bourne (A Future for Presentism [2006], Intro IIb)
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A reaction:
Must we choose? Two past events relate to each other, but there is a further relation when 'now' falls between the events. If I must choose, I suppose I go for the A-series view. The B-series is a subsequent feat of imagination. McTaggart agreed.
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14006
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Time flows, past is fixed, future is open, future is feared but not past, we remember past, we plan future [Bourne]
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Full Idea:
We say that time 'flows', that the past is 'fixed' but the future is 'open'; we only dread the future, but not the past; we remember the past but not the future; we plan for the future but not the past.
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From:
Craig Bourne (A Future for Presentism [2006], Intro III)
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A reaction:
These seem pretty overwhelming reasons for accepting an asymmetry between the past and the future. If you reject that, you seem to be mired in a multitude of contradictions. Your error theory is going to be massive.
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