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Logic sentence

  1. Oct 6, 2011 #1


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    Do the sentence "when the sun is shining then it is hot" is a logic sentence ?
  2. jcsd
  3. Oct 7, 2011 #2
    It merely states a proposition, rather than presenting any argument.
  4. Oct 7, 2011 #3
    is a meaningful declarative sentence, its content/meaning is often referred to as a proposition, it states a fact [in a peculiar manner]
    : "sun warms
    [the meaning of a sentence] a proposition has the property of being true/ false, not logical. [the unnecessary, redundant use of "when-then" may generate confusion].
    Logical, can be only an ordered set of sentences: a deductive/ inductive argument.
    A logical argument [has logical form] is valid and the conclusion, the conclusive proposition, is true
    Last edited: Oct 7, 2011
  5. Oct 9, 2011 #4
    You can maybe consider two possible settings: truth-functional logic and predicate logic.

    In TFL , an argument consists of two collections of sentences ; the first being the premises, and the second one being the conclusion, and where the premises purport to prove the conclusion, so that a truth assignment in {T,F} can be made of the sentence.
    Then maybe your statement is an argument with an empty set of premises, and you can declare it to be either true or false at will.

    In Predicate logic, I guess this could be a sentence within an interpretation,where there are predicates for 'hot', for shining, and maybe some non-logical inference rule that tells us what
    happens when the sunis shining, and , then, within the interpretation, one can conclude that the sentence is true or false.

    Maybe we could also use temporal logic to show the dependence of 'hotness' when the sun shining somehow.
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