110 comments

  • Yesterday

    Did I get it wrong?

    "All" is from group 1-necessity conditional indicators, where what follows immediately after the indicator, in this case "all", is the necessary condition. So, lawgic would be:

    All Jedi use the Force.

    J -> F

    Dooku use force:

    D -> F

    Dooku is Jedi:

    D -> J. This conclusion is not valid from the given premise.

    In case of "only", its from group 2-sufficiency conditional indicators. What follows immediately after the indicator, "only", is the sufficient condition. So, lawgic would be:

    Only Jedi use the Force.

    F -> J

    Dooku uses the Force.

    D -> F

    Chaining conditionals:

    D -> F -> J

    D -> J

    We can infer from the above that Dooku is Jedi, which is the conclusion in the argument.

    1
  • 6 days ago

    What has made this easier for me is realizing that all is not the same as only. All refers to everything of a certain group. Only is more strict about the rules.

    All dogs drink water. Other animals can drink water too.

    ONLY dogs drink water. No other animals drink water.

    1
  • Wednesday, Nov 12

    I am also confused by this but I am a little new to studying for this oldest trick in the book that keeps kicking my butt.

    All Jedi… Is that not a sufficient condition because they used “all”? All Jedi us the force so using the force is a sufficient condition of being a Jedi?

    Only Jedi…is that not a necessary condition because they used “only”? While using the force is a necessary condition of being a Jedi it is not sufficient to guarantee membership in the Jedi order simply because one uses the force?

    1
  • Thursday, Oct 02

    how is this any different than confusing sufficiency for necessity? I guess I don't understand why this is separate

    1
  • Thursday, Sep 25

    #feedback

    That last paragraph keeps tripping me up. A video would prob explain this better to avoid confusion.

    19
  • Thursday, Jun 26

    SO in form it would be

    A-->B

    B

    -------

    nothing - we cannot conclude anything about A

    I know this is simple but I want to make sure I am not missing it.

    7
  • Friday, May 23

    ... did you ever hear the tragedy of Darth Plagueis the Wise?

    27
  • Wednesday, May 14

    Keep it simple: Think about this:

    Only Arabic-speakers get PhDs. Chris is an Arabic speaker. Therefore Chris gets a PhD.

    If gets a PhD, then an Arabic Speaker, written

    PhD->Arabic-speaker

    Now here's where you don't want to mess up. It says Chris is in that "Arabic-Speaker" portion, or in other words, he's someone in the necessary condition position. But we can't work backwards. We can't say if Chris (the necessary) speaks Arabic then he gets a PhD.

    It's easier to see if we use three topics, as it builds on earlier lessons:

    A->B->C

    We can't say "if C, then B"

    13
  • Thursday, Mar 20

    Would you say this can be simplified to: "If the sufficient condition is false, the necessary condition can be true or false", and "if the necessary condition is true, the sufficient condition can be true or false"?

    31
  • Tuesday, Mar 04

    I do not understand the second example. If the conditional indicator is Only, that translates to logic Uses Force --> Jedi. Since Dooku uses the force, he triggered the sufficient and is a Jedi. This is a valid logic. But why did the text say I made up my own premise? If the conditional indicator is only, I did not make anything up did I? it's very confusing.

    11
  • Wednesday, Jan 29

    If it says all jedi use the force, and count doku uses the force. Its reasonable to assume that hes a jedi based on the premises. Dont understand why thats not valid

    3
  • Sunday, Jan 26

    #feedback Echoing what has been said, but videos would be really helpful. I don't understand what premise is being made up in the second half of these lessons.

    5
  • Tuesday, Jan 21

    Is it just me or does the x before A and B confuse anyone into thinking it's a negation.??... I know that negation is /A but x intuitively represents 'not' in my head agh!

    3
  • Friday, Dec 27 2024

    Pretty please bring back videos.... #Feedback

    14
  • Sunday, Dec 22 2024

    I really don't like the examples used in 7Sage. Why do you always stick to the Jedi/force/Yoda whatever thing? For people who never watch the show or have absolutely zero interest in it, it's not helpful for studying at all

    7
  • Sunday, Dec 22 2024

    Why is the Lawgic shorthand for Jedi and Force all of the sudden A and B instead of J and F in these examples? It makes it impossible to match english to the Lawgic shorthand in order to follow along. What are we doing here? #feedback

    8
  • Saturday, Dec 21 2024

    hello, i am a little confused bc in the conditional reasoning sets and supersets

    it said all mammals are cats. Garfield is a cat. therefore Garfield is a mammal. how is that a valid argument but not this. bc i thought the point of subset and superset. is the second premise proving that variable x (garfield) is a category of B, so we can conclude x is also a

    0
  • Sunday, Nov 17 2024

    Okay so this would be like saying:

    Every Californian lives on Main Street. Sarah lives on Main Street. Therefore Sarah lives in California.

    1
  • Monday, Oct 14 2024

    For anyone who is having a hard time grasping this: Just because something is B, doesn’t meant mean it’s A. In other words: Meeting the necessary condition doesn’t tell us whether something also = sufficient condition

    5
  • Monday, Sep 30 2024

    I think I see how negation is key here (someone correct me if I’m wrong).

    For example, if we take the statement…

    "All Jedi use the Force" and negate it, we get "Some Jedi don't use the Force.”

    Original: J → F

    Negated: J ←s→ /F

    This shows that it's possible for someone to be a Jedi without using the Force. So, going back to the original argument:

    "All Jedi use the Force. Count Dooku uses the Force. Therefore, Count Dooku is a Jedi."

    It is invalid because it’s possible that some Jedi don't use the Force. It is not enough evidence to say Count Dooku is a Jedi just because he uses the Force.

    0
  • Tuesday, Aug 27 2024

    Why is making up the premise for the second example a problem? The “only” tells us that “Jedi” is the necessary condition and then “Force” in the sufficient. Where is the problem in creating this premise?

    4
  • Wednesday, Aug 14 2024

    For anyone confused by the second example using "Only Jedi..." They are just trying to help explain that many students assume that when they see "all" in a statement that they confuse it with "only".

    The wording is confusing, but once I figured that out it helped to better understand this!

    20
  • Sunday, Jul 21 2024

    In the second example, "only Jedi use the Force" is translated into F -> J. Is this the equivalent to saying "One uses the Force only if they are a Jedi"?

    I was under the impression that "only" and "only if" are two completely different ideas, with "only" indicating a group one translation and "only if" indicating a Group 2 translation. Are they both group 2 indicators in that case? Can someone please clarify?

    0
  • Friday, Jul 19 2024

    WOULD THIS BE A VALID STATEMENT?

    Only dogs where collars. Mittsy is a cat. Therefore mittsy does not where a collar?

    0
  • Wednesday, Jul 17 2024

    #feedback

    videos and accurate time estimates, please!

    4

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