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Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! (Re: بريمة محمد)
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العزيز / بريمة أحيي عقلك الوثاب للمعرفة و أنت تتلمس طريقك وسط أفكار تبدو سهلة جدا ظاهريا بحيث تؤمن بصحة منطقك فيها بسهولة كما ينقدك الآخرون بنفس اليقين على فرض أن الفكرة واضحة البطلان !! .. هذا الموقف هو العلامة الفارقة للأفكار الفلسفية العميقة و هي هنا موضوع الـNonexistent Objects فهل هناك معنى للكلام عن نفي موجود ما إن لم يكن موجودا في الأصل ؟؟ .. هذا السؤال حير الفلاسفة عبر التاريخ و أنا شخصيا مقتنع بمعالجة الفيلسوف العظيم برتراند رسل له من وجهة نظر منطقية حيث أنه إستطاع في نظريته حول الأنماط المنطقية Logical Forms بيان أن الكلام عن إثبات/نفي ماهو غير موجود لا يعني منطقيا الإقرار بوجوده !! .. و بطريقة أسهل يمكنني مثلا أن أتبع نفس منطقك و أفتح بوستا أدعو فيه من لا يؤمن بزيوس كبير الآلهة لمطالعة الإثباتات على وجوده ثم أبتسم في وجوههم ساخرا !!
و حتى عودة أدعوك لمطالعة الإقتباس الآتي في شرح نظرية برتراند رسل ..
Quote:
Russell's most famous example of his “analytic method” concerns denoting phrases such as descriptions and proper names. In his Principles of Mathematics, Russell had adopted the view that every denoting phrase (for example, “Scott,” “the author of Waverley,” “the number two,” “the golden mountain”) denoted, or referred to, an existing entity. By the time his landmark article, “On Denoting,” appeared two years later in 1905, Russell had modified this extreme realism and had instead become convinced that denoting phrases need not possess a theoretical unity.
While logically proper names (words such as “this” or “that” which refer to sensations of which an agent is immediately aware) do have referents associated with them, descriptive phrases (such as “the smallest number less than pi”) should be viewed as a collection of quantifiers (such as “all” and “some”) and propositional functions (such as “x is a number”). As such, they are not to be viewed as referring terms but, rather, as “incomplete symbols.” In other words, they should be viewed as symbols that take on meaning within appropriate contexts, but that are meaningless in isolation.
If Russell is correct, it follows that in the sentence
(1) The present King of France is bald, the definite description “The present King of France” plays a role quite different from that of a proper name such as “Scott” in the sentence
(2) Scott is bald. Letting K abbreviate the predicate “is a present King of France” and B abbreviate the predicate “is bald,” Russell assigns sentence (1) the logical form
(1and#8242;) There is an x such that Kx, for any y, if Ky then y=x, and Bx. Alternatively, in the notation of the predicate calculus, we have
(1and#8243;) and#8707;x[(Kx and and#8704;y(Ky and#8594; y=x)) and Bx]. In contrast, by allowing s to abbreviate the name “Scott,” Russell assigns sentence (2) the very different logical form
(2and#8242;) Bs. This distinction between logical forms allows Russell to explain three important puzzles. The first concerns the operation of the Law of Excluded Middle and how this law relates to denoting terms. According to one reading of the Law of Excluded Middle, it must be the case that either “The present King of France is bald” is true or “The present King of France is not bald” is true. But if so, both sentences appear to entail the existence of a present King of France, clearly an undesirable result. Russell's analysis shows how this conclusion can be avoided. By appealing to analysis (1and#8242;), it follows that there is a way to deny (1) without being committed to the existence of a present King of France, namely by accepting that “It is not the case that there exists a present King of France who is bald” is true.
The second puzzle concerns the Law of Identity as it operates in (so-called) opaque contexts. Even though “Scott is the author of Waverley” is true, it does not follow that the two referring terms “Scott” and “the author of Waverley” need be interchangeable in every situation. Thus, although “George IV wanted to know whether Scott was the author of Waverley” is true, “George IV wanted to know whether Scott was Scott” is, presumably, false. Russell's distinction between the logical forms associated with the use of proper names and definite descriptions shows why this is so.
To see this we once again let s abbreviate the name “Scott.” We also let w abbreviate “Waverley” and A abbreviate the two-place predicate “is the author of.” It then follows that the sentence
(3) s=s is not at all #####alent to the sentence
(4) and#8707;x[Axw and and#8704;y(Ayw and#8594; y=x) and x=s]. Sentence (3), for example, is clearly a necessary truth, while sentence (4) is not.
The third puzzle relates to true negative existential claims, such as the claim “The golden mountain does not exist.” Here, once again, by treating definite descriptions as having a logical form distinct from that of proper names, Russell is able to give an account of how a speaker may be committed to the truth of a negative existential without also being committed to the belief that the subject term has reference. That is, the claim that Scott does not exist is false since
(5) ~and#8707;x(x=s) is self-contradictory. (After all, there must exist at least one thing that is identical to s since it is a logical truth that s is identical to itself!) In contrast, the claim that a golden mountain does not exist may be true since, assuming that G abbreviates the predicate “is golden” and M abbreviates the predicate “is a mountain,” there is nothing contradictory about
(6) ~and#8707;x(Gx and Mx).
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المصدر
الرجاء العودة للمصدر لمطالعة رموز المنطق التي تعذر إظهارها هنا مع الشكر
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العنوان |
الكاتب |
Date |
للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 06:49 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 06:58 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | ASHRAF TAHA | 01-26-13, 07:14 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 07:30 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | أيمن محمود | 01-26-13, 07:17 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 07:39 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | أيمن محمود | 01-26-13, 09:41 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 02:06 PM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | newbie | 01-26-13, 07:23 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | معروف حمدين | 01-26-13, 07:28 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 07:42 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 07:47 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 08:08 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 08:22 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | صلاح عباس فقير | 01-26-13, 09:55 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-26-13, 03:08 PM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | محمد قرشي عباس | 01-26-13, 10:20 AM |
Re: للذين لا يؤمنون بوجود الخالق .. الإثبات هنا ! | بريمة محمد | 01-27-13, 04:04 AM |
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