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The use of the word If

  1. Jul 22, 2004 #1
    The use of the word "If"

    The use of the word "if" implies multiple sernerios.

    "If you go through that door, you will die." implies that if you DON'T go through that door, you will live.

    While i was making my self some soup, my dad told me "There are some rolls in the cuboard if you want them." and i could not help but wonder "so... if i DON'T want them, they wont be there?

    I know of course that they will be there weather i want them or not. So why did he waste words adding an "if" if there was no differnce between any of the sernerios, and shorten it to "There are some rolls in the cuboard."

    It's silly i know but i had to post about it.
  2. jcsd
  3. Jul 22, 2004 #2
    Although this is an interesting way of looking at the word 'if', the logical way would be:

    If you don't go through that door, you might live. This is because that is not the only if that can apply to you. Think of it as a series of 'if, else' statements in programming code. If you don't go through that door, it doesn't mean that there is not another if that applies to you! For example, it could be that if you close the window you will die...

    As for 'There are some rolls in the cupboard if you want them', this is more something to do with speech. It is best interpreted as: You are being informed that the rolls are in the cupboard, IN CASE you might want them. If means more 'IN CASE' than a proper if.

    But this is only my understanding of it!
    Last edited: Jul 23, 2004
  4. Jul 22, 2004 #3
    hmm... that doesn't improve much on the situation, since again, the cookies are there in case you want them, and implicitly not if you don't...

    the german version would be translated to:
    should you have cravings for cookies, there are some in the cubboard... which maybe sounds weird in english, but doesn't imply as much...
    most other languages i know, though, have this double meaning... not a whole lot to do about it, except accepting it as just another ligual situation where the exact meaning is implied in its contextuality...
  5. Jul 22, 2004 #4
    Use a mathematical proof using an if, then statement.

    i.e- as in your statement: If you want them, then there are rolls in the cupboard.

    Look at it this way. Use the comma like a point to stop and think. If you want them, (rolls): [place to answer question].
    Then there are rolls in the cupboard.

    So it's like saying "if you want them or not, then there are rolls in the cupboard."

    Interesting topic.

    Paden Roder
  6. Jul 22, 2004 #5
  7. Jul 23, 2004 #6
    I chose not to want them, and then i opened the cuboard to see if they was gone, but i guess they called my bluff cos they was there. o_o
  8. Jul 23, 2004 #7
    What other reasons might people add that little attachment "...if you want"?
  9. Jul 23, 2004 #8
    "If you want some rolls, they are in the cuboard." is not the same as "There are some rolls in the cuboard if you want them."

    If you want some rolls (or if you dont) they are in the cuboard."

    There are some rolls in the cuboard if you want them (However, if you dont want them...)

    I believe "If" is an alternative, or a however. Using "If" with no differnce between situation is like the following:

    You can see "If" your eyes are open, however, if your eyes are shut, you can see.

    Clearly that makes very little sence.
  10. Jul 23, 2004 #9
    You are correct, the rolls are not there if you don't want them. More correctly, they are not there if you don't open the cupboard and observe them. Until this occurs, the rolls are merely in a quantum superposition of all possible states. :wink:

    On a more serious note, the specific context of "if" which you've mentioned I believe implies a "then help yourself" at the end of the sentence. e.g.: "There are some rolls in the cuboard, if you want them then help yourself."

    In regards to the original context, I believe it's a false assumption that you won't die if you don't go through the door. The only information being provided is what will happen if you DO go through the door. Nothing is revealed about what will happen if you do not. Granted, that the statement's purpose is lost if you will die either way, which would suggest there ARE alternatives to going through the door that would lead to outcomes other than dying. However, that is not necessarily the case in order for the statement to be true. In fact, I've seen many comedy routines based on providing an "if-then" statement in a situation where a particular outcome is unavoidable.
  11. Jul 23, 2004 #10


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    "Because there is the possibility that you might want to eat one or many, I am informing you that there are rolls in the cupboard."

    That would the proper way to construct such a sentence.
  12. Jul 24, 2004 #11


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    That's wrong, it's called denying the antecedent. If you go through that door, you will die. If you don't go through that door, you could just suddenly have an anvil dropped on you, and still die. In fact, as long as you are human, you will die, going through that door is just one way to die.

    "If you want them, they are there" DOES NOT imply, "if you don't want them, they are not there." Again, it's the same fallacy. Now, surely you know how to have a reasonable conversation, and can guess that what your dad meant was:

    There are some rolls in the cuboard so you know where to look for them if you want them.

    This has nothing to do with logic, it's just how we talk. Normally, I don't just go walking around stating facts. I won't walk into the kitchen and tell a guest that there's juice in the fridge, but if I see the guest sitting down to eat and think he or she might be thirsty, I might say, "there's juice in the fridge if you want it." It's how we talk, you might be looking for a psychological, cultural, or linguistic answer, it has nothing to do with logic.
  13. Jul 26, 2004 #12
    Gara, there are two different logical statements:

    1) There are rolls if you want them.
    2) There are rolls if and only if you want them.

    There are different symbols for these different kinds of "if"s (though I don't know how to produce those symbols on this forum) because they mean different things.

    Logical charity is necessary when speaking as we commonly do, since we often just use the word "if" without giving any thought to whether we mean "if-then" or "if and only if - then").
  14. Jul 27, 2004 #13


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    You can use iff for "if and only if."
  15. Jul 27, 2004 #14
    AKG, how can you say this has nothing to do with logic, when languish is purely logic based? With out logic, languish would just be random words strung together.
  16. Jul 27, 2004 #15


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    Because language isn't purely logic based. You had to read between the lines to understand what your father was saying, that's a very real part of language (reading between the lines) because normally we have humans talking to each other, not robots. If it were robots, then language would have to be purely logical (unless robots got smart enough), but otherwise, you have to read between the lines, something that has nothing to do with logic. By pure logic, you can't deduce what he meant, but because (hopefully) you're an intelligent human being, you can understand what he said without him having to spell it out.
  17. Jul 27, 2004 #16
    Actually, AKG, one could include the amount of "world knowledge" (aka "common sense") that is require to interpret what one "means" when they say something -- as in Gara's original example -- as a very real and valuable part of logic itself. At least, it seems quite related to the principle of logical "charity", which is indeed invaluable to rational discussion.
  18. Jul 27, 2004 #17


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    It depends on how you want to define things. I think if you want to be very lax in your definitions, you can group logic and common sense together as they are both things you use to make sense. But really, knowing what her father was saying really just takes one to be familiar with the culture and common use of the English language, and not any type of deductive reasoning or rationality. Like I said, to understand what he was saying has more to do with psychology, culture, and the common use of language, and saying that one who knows these things is logical because of it is a very loose, if not useless definition of logic. But that's just my opinion.. you can use words how you like.
  19. Sep 12, 2004 #18

    1. In the event that: If I were to go, I would be late.
    2. Granting that: If that is true, what should we do?
    3. On the condition that: She will play the piano only if she is paid.
    2. Although possibly; even though: It is a handsome if useless trinket.
    3. Whether: Ask if he plans to come to the meeting.
    4. Used to introduce an exclamatory clause, indicating a wish: If they had only come earlier!
    A possibility, condition, or stipulation: There will be no ifs, ands, or buts in this matter. "

    There are multiple definitions to the word "if".You cannot imply one definiton to all scenario's. "If"'s inverse is not always going to be true. Such as:

    "If he pulls the trigger to the gun in his mouth he will die. If he doesn't then he will live". But I can't imply the same definition of "if" to: "There are rolls in the pantry, if you want them. There aren't any rolls in the pantry, if you don't want them."

    I think it's a case of inverses, converses, and contrapostives. What you stated in the first post (and what we are debating about) is an inverse of "There aren't any rolls in the pantry, if you don't want them."
  20. Sep 14, 2004 #19


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    Let's just break it down to:
    If A then B
    This does not mean A = B, it means If A then B. That means not B won't necessarily result from not A.
  21. Sep 19, 2004 #20


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    "...if you want them" implies permission in this case. This was actually conserving words by not stating the lengthier and more accurate version, "There are some rolls in the cupboard. If you want them, you may help yourself." Or, "If you want to eat them, you have permission to take as many as you'd like." Of course, to conserve on words, the better approach would have been to ascertain your interest in the rolls before wasting time providing their location..."Would you like a roll with your soup?" If you answered yes, then he could tell you, "They are in the cupboard." If you answered no, there would be no need to explain further their location.
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