7.1 Rules of Implication I

[@htg04]

You and these videos are the ONLY reason I passed Logic Class. Thank you.

[@fezilenjomane9065]

I've been really struggling with this section. I've watched this vid several times today, my quiz is due tomorrow. I finally got it😍 very nice. Thank you very much Dr god bless 👏

[@harperjericho7751]

you have no idea how much this has helped me. i was struggling so hard in my logic class because my professor went so quickly and I'm not a math person to begin with, you are a absolute lifesaver, sincerely, thank you.

[@tayvahstraub6007]

You make more sense than my professor. He doesn't make videos, he writes a whole book and calls it a lecture. You sir are saving my life

[@JonathanMalk]

THANK YOU SIR! My "professor" is a graduate student who likes to just post the whole solution at once and assume that we understand it. Meaning I did not understand the steps necessary to reach said conclusion. Thank you for going step by step and actually explaining this! Bless you sir!

[@PhilosophicalTechne]

You are quite welcome! Thank you for the kind comment.

[@somerville77]

I supposedly go to one of thee most prestigious schools in America and yet my Proff and GSI are both completely incompetent and useless. Thank you very much man, now i stand at least a fighting chance at this next exam.

[@DUSTINPARQUE]

Phil 180? haha

[@somerville77]

yeah...lol i thought it would be a somewhat blowoff humanities and its actually quite difficult

[@eropp157]

Professor Thorsby, you are my hero.

[@noura5975]

I just wanted to truly thank you for teaching me this, I have had a really hard time trying to understand this and have studied well over a week with no results. Watching this one video cleared everything up for me, thank you so much

[@MattPryze]

To speed things up, click the gear icon on the video and change the speed to 1.5

[@wesbaugher]

anyone else having trouble with this section, i find it really difficult

[@XanderMap]

I feel like logic professors don't see the need to still express these concepts visually throughout, as in previous chapters. I can't visualize these rules in my head.

[@whitb62]

It’s proof writing, it’s hard by nature. But the more you practice the more it makes sense. It’s unattainable without active participation.

[@GenevieveRamirez]

OH MY GOODNESS. You've have made this entirely clear. My entire class seriously failed our test on this chapter because no one understood it. I'm now helping everyone 'cause of you B) Thanks so much!!

[@yeromey1]

thank you so much. Your a gentleman and a scholar I couldnt have done it without your help!!!!

[@DozingDreamer]

I finally get the material because you were so clear!!! THANK YOU!!!

[@schylerrenee7655]

god bless you, i wouldn't be able to solve these puzzles without your help

[@metube2634]

If you haven't read sec 6.6, I'd advise that you do before doing sec. 7.1.

[@sherrybrusseau9145]

Thank you for posting these videos, this makes such better sense now. Much appreciation!

[@dariusniles3251]

Thank you!!! I was really confused until now!! It all makes sense now!!

[@ramnozack]

"I need to get that D" -Mark Thorsby 2012 49:35

[@advenco344]

Legendary

[@jessicapaige7577]

These videos pretty much saved me. they were hard to find, because the proofs are called something else in my book, but I just could not figure this out by myself to save my life.

[@OMFGitsAdrianna]

i will not fail my logic class now because you made me understand thank you! hopefully I can pass my exam and get a good enough score to pass the class and graduate. I am eternally grateful for your videos.

[@sleepyd1231]

Thanks mark, just a thought but you may want too contact KhanAcedamy as they may be willing to help spread you're course series

[@edwinrelf8454]

Thank you for this series of lectures. You are clear and thorough.

[@richieb1515]

Thanks man this video is after helping me more than anything else I could find.

[@federicocontreras6352]

My professor should call you and ask for advice on how to teach logic. He makes no sense and goes through an entire chapter (not section) in an hour or two and expects us to learn everything. Honestly I learn because of you and not my crummy professor. Thanks prof. Throsby!!!!

[@dionysussatyr7937]

Thanks man, I really appreciate the efforts you put into making these videos. I'm so grateful ❤️

[@Joan10986]

i dont understand so much english but i always undesrtand your class. thanks.

[@cristianhernandez7591]

THANK YOU SO MUCH. OH MY GOODNESS. That was fantastic. Super well explained. I finally understand. These are so fun now :)

[@dontay03]

Thank you so much. I got a 104 after watching this and the class average was around a 50.

[@CameronSmithAU]

Mark, you are an absolute legend!

[@folke8327]

Great! Thanks! This stuff is so much better in video than in text

[@konflictification]

Who else plays these on 1.5X speed? Great tutorials btw!

[@ShaareiZoharDaas]

Love this am using it to understand what I am speeding through this summer.

[@shriyas3432]

Meeee

[@kolt2928]

Thanks Mark your the man, totally helped me out. By far your a lot bette than my teacher.

[@okayypaulaaa]

I have an exam tomorrow morning. Thank you!

[@rosie11954]

You should open up a Patreon so we can give money as thanks. This is excellent!

[@temporartepom9046]

Hi, great video, i almost overlooked it as i did not realise it was about natural deduction until you said that i was about that in the previous video

[@marooqi]

@ 40:14 when you did those exercises in section ii, how do you know what youre trying to end up with thout the conclusion? I know you are limitred to one step, are you just looking for the first proof but really there would be a couple more, ending up with the conclusion? Thanks for including one demo of the latter problems btw!

[@lhoughinmagluyan8168]

Thank you. I am enlightened..

[@fondizzie]

thank you so much. crystal clear with practice.

[@shrubbylubes]

u just saved my LIFE thank u

[@francescopiazza4882]

Great lesson!

[@varduhiavetisyan3910]

Thank You very much, it was very helpful.

[@emmanuelvaldez7753]

thank you!!! you are saving my grade

[@sweetredrose2100]

A Concise Introduction to Logic By Patrick J. Hurley

[@johnsonken96]

Side Note: your handwriting is great, especially when compared with other videos trying to explain these same concepts (only with terrible handwriting)

[@antandteoa7682]

Thanks man this video extremely helped!!

[@isaacroberts7752]

Is there any difference between rules of implication and rules of inference?

[@sweetredrose2100]

at 40:54 you write for the justification for line 5, 1, 4 MP. it should read 2, 4 MP.

[@whitb62]

I think it should actually be just N 3,4 DS.

[@brittneylarmon4165]

What does the double negation mean? For example, #13. --F

[@whitb62]

It just means the negation of negation f, which is f. It just looks funny. The negations cancel each other out.

[@isaacroberts7752]

At about 28.00 you say if F therefore I. Step 5 reads ~F. Doesn't that make step 8 incorrect? What did I miss?

[@CFSWarrior]

I still don’t understand this. :/ You helped me understand truth tables perfectly though ^.^ I appreciate your videos. I am just having a lot of trouble understanding this.

[@TheDsmith32]

your a life savor

[@migtrewornan8085]

I think this is a mistake too ~J v P, ~J / ~P he does the opposite concluding P and this is invalid.

[@carlomarx7412]

Yes. Here: kzbin.info/www/bejne/bqjWl6Wqdr2SpKc It should have been If S then J Not J Therefore not S.

[@daniachrisantia3086]

this video helps! thank you so much:)

[@aprylboo7944]

ok I have a problem on my logic coach and I can't seem to figure out a way to work through all the proofs it is : (L (triple bar)N) Horseshoe C / (L (triple bar) N) v (P(horseshoe) ~E) /~E (horseshoe) C / ~C // ~P. I have no idea where to even start seeing how I have yet to encounter a triple bar while working through proofs in section 7.1 can anyone help me understand what to do. I am lost.

[@whitb62]

So I don't think the biconditional (≡) really matters in this proof. Here is a proof I found for your problem, starting with the first inference: 5. ~(L≡N) 1,4 MT 6. P ⊃ ~E 2,5 DS 7. ~~E (Also just E) 3,4 MT 8. ~P 6,7 MT

[@kingmoe1545]

that was awesome thnx

[@dongzhao3343]

Hi Mark, I found a problem at 39:00 on problem #6, I used 2,3 MT to get the fourth statement ~S, please correct me if I am wrong. Thanks.

[@amybethh1]

I got 2,3 MT as well. I believe he made a mistake because DS should have only had one negated J.

[@whitb62]

You're right, his conclusion is wrong.

[@PriyaGupta-iy6ne]

you used premises 1 twice and you said that premises should be used once. can you explain me this?

[@Wtfgtfoooo]

thank you.

[@Sometimesiwanttoread]

can someone tell me how this is important to know in the real world?

[@whitb62]

All mathematical proofs and computer science are based on these rules. It is the literal foundations.

[@dgammelg]

thanks

[@psychedforlife7176]

I haven't taken trig so that wasn't helpful to me. :(

[@Zen-lz1hc]

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