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From: Immortalist on 3 Jul 2010 21:26 The distinction between contingent and necessary statements is one of the oldest in philosophy. A truth is necessary if denying it would entail a contradiction. A truth is contingent, however, if it happens to be true but could have been false. For example: Cats are mammals. Cats are reptiles. Cats have claws. The first statement is a necessary truth because denying it, as with the second statement, results in a contradiction. Cats are, by definition, mammals - so saying that they are reptiles is a contradiction. The third statement is a contingent truth becuase it is possible that cats could have evolved without claws. This is similar to the distinction between essential and accidental qualities. Being a mammal is part of a cat's essence, but having claws is an accident. http://atheism.about.com/library/glossary/general/bldef_contingentstatements.htm A proposition expresses a necessary truth if and only if denying that proposition would result in a self-contradiction. On the other hand, a proposition expresses a contingent truth is one which can be rationally denied without resulting in any self-contradiction. Thus, for example, the logical principle of the law of identity (a = a) is a necessary truth because in order to rationally deny it, one would have to assume its truth (for example, in order to deny it, you have to assume that it is identical with itself, otherwise what are you denying?) - a self-contradiction. http://atheism.about.com/library/glossary/general/bldef_contingenttruths.htm The necessary/contingent distinction concerns the modal status of a statement. To say that a statement is necessarily true is to say that it must be true or that it is true in all possible worlds. A statement is contingently true in case it just happens to be true because of the way the actual world is. Traditionally, there are three "modes" or "moods" or "modalities" represented by modal logic, namely, possibility, probability, and necessity. http://en.wikipedia.org/wiki/Modal_logic
From: bigfletch8 on 3 Jul 2010 22:19
On Jul 4, 9:26 am, Immortalist <reanimater_2...(a)yahoo.com> wrote: > The distinction between contingent and necessary statements is one of > the oldest in philosophy. A truth is necessary if denying it would > entail a contradiction. A truth is contingent, however, if it happens > to be true but could have been false. For example: > > Cats are mammals. > Cats are reptiles. > Cats have claws. > > The first statement is a necessary truth because denying it, as with > the second statement, results in a contradiction. Cats are, by > definition, mammals - so saying that they are reptiles is a > contradiction. The third statement is a contingent truth becuase it is > possible that cats could have evolved without claws. > > This is similar to the distinction between essential and accidental > qualities. Being a mammal is part of a cat's essence, but having claws > is an accident. > > http://atheism.about.com/library/glossary/general/bldef_contingentsta... > > A proposition expresses a necessary truth if and only if denying that > proposition would result in a self-contradiction. On the other hand, a > proposition expresses a contingent truth is one which can be > rationally denied without resulting in any self-contradiction. Thus, > for example, the logical principle of the law of identity (a = a) is a > necessary truth because in order to rationally deny it, one would have > to assume its truth (for example, in order to deny it, you have to > assume that it is identical with itself, otherwise what are you > denying?) - a self-contradiction. > > http://atheism.about.com/library/glossary/general/bldef_contingenttru... > > The necessary/contingent distinction concerns the modal status of a > statement. To say that a statement is necessarily true is to say that > it must be true or that it is true in all possible worlds. A statement > is contingently true in case it just happens to be true because of the > way the actual world is. > > Traditionally, there are three "modes" or "moods" or "modalities" > represented by modal logic, namely, possibility, probability, and > necessity. > > http://en.wikipedia.org/wiki/Modal_logic How the mind loves to try to 'freeze'an ever unfolding set of events. This is a deslusional entity looking for reality , so is to be expected. A cat is an accumulation of cells complying 'temporarily' a genetic code providing a specific set of experiences for 'that which is cat'. The American Indians didnt refer to 'a buffalo' but 'buffalo spirit', for which they held great reverence.They knew hat they were talking about, contingent on their wisdom ! BOfL BOfL |