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4.7: Formalizing your Arguments

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    29608
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    24 Formalizing your Arguments42

    Now it’s time for you to apply all of your formal logical skills. It is good practice to look at arguments you see in a formal, deductive fashion whenever possible because it allows you to see if the reasoning employed is valid or falls afoul of a fallacy. It also shows you exactly where and how the argument goes wrong. If it is valid, then the next step is checking it for soundness (at the premises actually true?) Illustrating the truth of premises usually falls on the shoulders of inductive logic, which is covered in the next chapter.

    What you should do now is try and formalize an argument in your own writings. Do the following:

    1) Identify your conclusion. 2) Identify your premises. 3) Break down your premises into the smallest units you can and symbolize each claim. 4) Symbolize each logical statement you make in your argument. 5) Structure the argument in a formal fashion to make the flow of your statements lead naturally to your conclusion. 6) Check it for validity and note any standard forms your argument employs, citing them to show its validity. 7) Check to see if any of your claims are not needed to draw your conclusions from your premises. If so, remove those claims.

    For example, if I were to argue,

    LED lights are very cost efficient. They can also produce a range of natural-looking light. They didn’t use to look so natural, but they do now. Regular lights are cheaper, but they don’t last as long. LED lights use less energy than other light sources. Therefore, you should buy LED lights instead of other light options.

    1) Conclusion: You should buy LED lights instead of other light options. (B) 2) Premise 1: LED lights are very cost efficient. (C)

    Premise 2: LEDs can also produce a range of natural-looking light. (N)

    Premise 3: LEDs didn’t use to look so natural, but they do now.

    Premise 4: Regular lights are cheaper, but they don’t last as long.

    Premise 5: LED lights use less energy than other light sources. (E)

    3) Premise 3a: LEDs didn’t use to look so natural. (~P)

    Premise 3b: LEDs look natural now. (L)

    Premise 4a: Regular lights are cheaper than LEDs. (R)

    Premise 4b: Regular lights don’t last as long as LEDs. (~T)

    4) See parentheses above 5) C

    N

    ~P

    L

    R

    ~T

    E

    B

    6) This argument is not valid at all and is just a bunch of statements. To make it cleaner, I should try to do something like the following:

    ~T

    E

    (~T&E)>C

    N

    (C&N)>B

    B

    Now it uses two modus ponens and some conjunctions to reach the conclusion. Doing it this way also tells me I can clean up how I write my argument to be:

    Regular lights don’t last as long as LEDs. LED lights use less energy than other light sources. If LEDs last longer than other light sources and they use less energy, then they are more cost efficient. LEDs produce natural-looking light. If LEDs produce natural-looking light and are more cost efficient, then you should buy LEDs instead of other light options. Therefore, you should buy LEDs instead of other light options.

    7) I already did this in 6 and eliminated a number of claims (~P, R, etc.) that didn’t matter when what I’m concerned with doing is making a valid argument to reach my conclusion. However, there are still problems in how I have phrased my argument that get in the way of it being as strong as it could be. Can you see how I can word it better to make it stronger?

    This page titled 4.7: Formalizing your Arguments is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Noah Levin (NGE Far Press) .

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