Thanks. This is the only video i could find where the instructor himself/herself was not confused during the explanation. So eloquent. Wasted half an hour. Finally got the understanding in 5 minutes from here.
This is a bit more complicated explained than it could be. Here's a quote from another site: "Remember that "implies" is equivalent to "subset of". It works in exactly the same way: "if an element is in the subset (e.g A), it MUST also be in the superset (e.g. B)". By definition, it is impossible that an element is in the subset, but not in the superset. That's the P=1, Q=0; P=>Q = 0 case. In fact, "A ⊆ B" means that a ∈ A implies that a ∈ B. If a is not in subset A then you can't draw any conclusions on whether a is in the superset B. That's how I keep remembering it." So understanding implications with unions is easiest (to me at least), and U, x, A and B is just mental gymnastics that is unneeded here.
It does not work the other way around. " If he is a good explicator of implication, he is a professor at IIT." cannot be true as there are professors at other universities or even non-professors who could do a good job. This also shows the converse is not equivalent to the implication.
There are 3 places an element x can be in the Venn diagram of "U the universe, a bigger circle B, and a smaller circle A completely in B". 1. x is outside B (and therefore outside A). This is the first line of the truth table where q=0 and q=0). 2. x is inside B but outside A. This is the second line of the truth table. 3. x is inside A (and therefore inside B). This is the last line of the truth table. The above 3 lines are T because they are possible according to the Venn duagram, but the third line is F because it is impossible. You cannot put x in A without it also in B.
Thank you, @kevinton5181. This is the most useful reply to the most helpful explanation of logical implication I've found: three lines of the truth table are "T because they are possible according to the Venn diagram." (One typo: in Point 1, you mean "where p=0 and q=0", yes?)
So implication is more like "maybe" or "can be"? If you are not born in NY (0) then maybe you are also not born in US (0) which is true (1) If you are not born in NY (0) then maybe you are born in the US (1) which is also true (1) But if you are born in NY (1) you cannot be born outside US (0) so that's false (0) And definitely if you are born in NY (1) you are also born in the US (1) which is also true (1)
I have a trick to remember this, think of P as question Q as answer and P->Q as Marks: P(question) Q(answer) P->Q(Marks) 0 (Wrong Question) 0 (wrong answer) 1 (Awarded) 0 (Wrong Question) 1 (right answer) 1 (Awarded) 1 (Right Question) 0 (wrong answer) 0 (No Marks) 1 (Right Question) 1 (Right Answer) 1 (Awarded)
Can you just answer why "true" (according to your definition) is what "possibly happens" and "false" is what "never happens"? As far as I understand "true" is what "must happen in any case for every test"
Honestly, this explanation tops all other explanations of implication I've seen. I don't like just memorizing stuff, I want to understand it too, so this helped me thank you.
I just remember implications like some one is doing a little trolling in twitch chat :tf: makes a troll face so t f is the exception with 0. but now I know why that is the case.
Let's imagine that I have a set of four cards laid on the table, each of which shows a certain color on one face, and shows a certain number on its opposite face. And I state that "In this set, if a card shows an even number on one face, then its opposite face is red". In real life, this statement makes sense only when there is at least one element in the set that satisfies the first condition, and it is true only when each card that satisfies the first condition also satisfies the second condition. On the other hand, in logic, this statement can make sense even if there is no element that satisfies the first condition and it is true only when each card verifies any of the following clauses: a) The first condition is true and the second condition is true, b) the first condition is false and the second condition is true, and c) the first condition is false and the second condition is false. Because in that way we guarantee that there are no cards that contradict the implication. So, in logic, this statement means "There are no cards that verify the first condition but not the second" (In this case, we do not need any card to fulfill the first condition for this statement to make sense.) Furthermore, if there exists at least one card that satisfies the first condition, then by guaranteeing the logical implication, we guarantee that that or those cards also satisfy the second statement. That is, we’re guaranteeing that each card that satisfies the first condition also satisfies the second condition. So we can say that, in this context, the logical implication and the real life implication actually mean exactly the same thing when there exists at least one card that satisfies the first condition. PD: Question for you, ¿would they mean the same thing if there were no cards that satisfy the first condition?
Most intuitive explanation of implication I've ever come across. Boatloads of gratitude
Thanks. This is the only video i could find where the instructor himself/herself was not confused during the explanation. So eloquent. Wasted half an hour. Finally got the understanding in 5 minutes from here.
The Best Explanation I could find so far, Thank You Sir
Thank you so much! German University Students would be toast without Indians xD
*worldwide university students would be toast without Indians XD
bro I've been tyring to understand this for 2weeks.
Finally found the right video.Without this video I would still be having confusion
Perfectly explained, my hero.
Simplest most understandable video I've come across on logic gates. Thank you so much
Thank you for the short and well explained video, the confusion you talked about was precisely what I struggled with.
Bravo!!! Bravo!!! Such brilliant explantion.
This video put a smile on my face. I also finally understood implication. 👑 --> you deserve this king
Was so easy to understand. I like how he broke it down into simple terms.
this explanation should be played at the befinning of all implication lectures, thank you. will definitely subscribe, mark
Bravo...such a brilliant explanation with less time 🎉🎉🎉
Thanks a lot! I was struggling to understand this concept for some time. This explanation makes total sense.
The best explanation from one of the best professors of DM
Brilliant explanation! I looked up in many books still couldn't understand but you made me understand within the first 2 minutes of your video ! 🕺
This is a bit more complicated explained than it could be. Here's a quote from another site: "Remember that "implies" is equivalent to "subset of". It works in exactly the same way: "if an element is in the subset (e.g A), it MUST also be in the superset (e.g. B)". By definition, it is impossible that an element is in the subset, but not in the superset. That's the P=1, Q=0; P=>Q = 0 case. In fact, "A ⊆ B" means that a ∈ A implies that a ∈ B. If a is not in subset A then you can't draw any conclusions on whether a is in the superset B. That's how I keep remembering it."
So understanding implications with unions is easiest (to me at least), and U, x, A and B is just mental gymnastics that is unneeded here.
Thanks for the great explanation! You are great teacher.
Basically, when we derive a true, it is not a definite casual relationship. That's all about it.
I have been confused with this for years Sir..Thanks a lot
Thank you! Your explanation made this concept understandable to me
This deserves more views wow
you taught so well,now i'm understand clearly,Thank you prof
Thanks it was so confusing initially to me, but your example reveled the whole concept.
you are a lifesaver dude, thanks
very easy to understand In this way 🎉🎉🎉 thank you so much.
One of the best explanation ❤
Great example to explain this concept. Thanks!
Ofcourse - he is an IIT Professor
If he is a professor at IIT, then he is a good explicator of implication.
It does not work the other way around.
" If he is a good explicator of implication, he is a professor at IIT." cannot be true as there are professors at other universities or even non-professors who could do a good job.
This also shows the converse is not equivalent to the implication.
There are 3 places an element x can be in the Venn diagram of "U the universe, a bigger circle B, and a smaller circle A completely in B".
1. x is outside B (and therefore outside A). This is the first line of the truth table where q=0 and q=0).
2. x is inside B but outside A. This is the second line of the truth table.
3. x is inside A (and therefore inside B). This is the last line of the truth table.
The above 3 lines are T because they are possible according to the Venn duagram, but the third line is F because it is impossible.
You cannot put x in A without it also in B.
Thank you, @kevinton5181. This is the most useful reply to the most helpful explanation of logical implication I've found: three lines of the truth table are "T because they are possible according to the Venn diagram."
(One typo: in Point 1, you mean "where p=0 and q=0", yes?)
You are right. Thank you for your correction.❤
So implication is more like "maybe" or "can be"?
If you are not born in NY (0) then maybe you are also not born in US (0) which is true (1)
If you are not born in NY (0) then maybe you are born in the US (1) which is also true (1)
But if you are born in NY (1) you cannot be born outside US (0) so that's false (0)
And definitely if you are born in NY (1) you are also born in the US (1) which is also true (1)
Nice explanation sir...thankyou
Best explanation 👌
very good explanation...
So we have to assume |q|>|p| for this to count?
Also, thank you for presenting this video in such a wonderful way!
thank you for well explained video
Thank you, it really helped me!
I have a trick to remember this, think of P as question Q as answer and P->Q as Marks:
P(question) Q(answer) P->Q(Marks)
0 (Wrong Question) 0 (wrong answer) 1 (Awarded)
0 (Wrong Question) 1 (right answer) 1 (Awarded)
1 (Right Question) 0 (wrong answer) 0 (No Marks)
1 (Right Question) 1 (Right Answer) 1 (Awarded)
if p is a subset of q, wrong answer is not subset of right question ?
Thank you so much. Very amazing explanation.
Best explanation sir
Can you just answer why "true" (according to your definition) is what "possibly happens" and "false" is what "never happens"? As far as I understand "true" is what "must happen in any case for every test"
thank you for simple explanation :)
Honestly, this explanation tops all other explanations of implication I've seen. I don't like just memorizing stuff, I want to understand it too, so this helped me thank you.
So, those truth tables are not unambiguous?
Nice explanation.
best explaination!
thanks man you saved me I have an exam tomorrow
great elaboration.. Thank you.
I just remember implications like some one is doing a little trolling in twitch chat :tf: makes a troll face so t f is the exception with 0. but now I know why that is the case.
Let's imagine that I have a set of four cards laid on the table, each of which shows a certain color on one face, and shows a certain number on its opposite face. And I state that "In this set, if a card shows an even number on one face, then its opposite face is red".
In real life, this statement makes sense only when there is at least one element in the set that satisfies the first condition, and it is true only when each card that satisfies the first condition also satisfies the second condition.
On the other hand, in logic, this statement can make sense even if there is no element that satisfies the first condition and it is true only when each card verifies any of the following clauses: a) The first condition is true and the second condition is true, b) the first condition is false and the second condition is true, and c) the first condition is false and the second condition is false. Because in that way we guarantee that there are no cards that contradict the implication. So, in logic, this statement means "There are no cards that verify the first condition but not the second" (In this case, we do not need any card to fulfill the first condition for this statement to make sense.)
Furthermore, if there exists at least one card that satisfies the first condition, then by guaranteeing the logical implication, we guarantee that that or those cards also satisfy the second statement. That is, we’re guaranteeing that each card that satisfies the first condition also satisfies the second condition.
So we can say that, in this context, the logical implication and the real life implication actually mean exactly the same thing when there exists at least one card that satisfies the first condition.
PD: Question for you, ¿would they mean the same thing if there were no cards that satisfy the first condition?
1000th like 😁
best best best!
4:30 xD . no cap good video
thank you iyanger sir I recognised you
thank you so much u made it really simple
Thanks keep going on
Thank you 👍
awesome explanation
I think this is more of a pseudo-explanation that helps us remember the truth table (WICH IS FINE). Not an actul explanation.
I think the same
so impiies = something possible happened, will get 1, will get 0, when something impossible happened
Not impossible is possible? Just clarifying a double negative
legend
Thank you very much good sir :)
The true nature of implication is not entailment but opposition: ua-cam.com/video/supEdKORfNw/v-deo.html (English subtitles available)
Helps a lot
thankyou
Thank you so much
THANK YOU
binod was here
thank you from the future
thank youuu
1 & 2 say "maybe", not "true'.
I love you
please don't break your head :D
Trash