It's 4 years later, but I have to agree. I got a problem that said "Show a resolution refutation proof tree" and had no idea what that was nor how to make it, and this was the best and only place that actually showed how to make one.
this is literally the only good explanation for proof trees that I found and its honestly far better than my university lecture, thank you so much and greetings from germany!!!
I decided, for some ungodly reason, to take a six-week (online!) summer course for logic and I'm getting a bit overwhelmed. Your video was by FAR the most helpful and easy to follow. I just stumbled across it. You've got a like and subscribe for me. I just hope you have other videos that will help with the rest of my classwork! Going to look right now! Thank you!
This video was very well organized, and I like how you explained the reasoning behind many of the moves and anticipated many of the possible confusions in the video. Thank you for this.
Thank you so much! Your video is a life saver, the explanation is clear, short and so much more understandable than any other explanation I looked into. Thank you!!
I'll personally be done with the course in 2 days but I found that there's a lack of instructions for truth tree tests of other sort. Like using a truth tree to test for truth-functional falsehood, tautologies, and truth-functional indeterminacy. Thanks for such a useful channel.
I agree with the other comments, this was very thorough crystal clear, and understandable, now just up to me to learn all the operations, haha... Thank you...
Wow, crystal clear explanation for truth trees! :D I'm just wondering why couldn't the ~D in the trunk of the tree close off the D in the branch? In the final step, that branch of the tree was eventually closed off anyway. :/
Because the ~D in the trunk is not by itself, it's part of a longer formula. Imagine if the ~D in the trunk had been part of the formula Bv~D; in that case the tree would had at least one open branch.
I continue on listening to your video series. I have a general question. Are truth trees, truth tables and the proof method, explained in the videos from 1.1-3.10 substitutable methods for testing validity in propositional logic? I am listening to the playlist because concepts in logic (trees, tables, predicate logic, relations) are to some extend a building block in set theory, which on turn is necessary for measure theory, which is useful in integration in stochastic calculus, which in turn is necessary in financial valuation. I tried to skip lessons on logic, set and measure theory, but found it somewhat confounding, how stochastic calculus are applied in financial books without explanation in measure theory. I will be grateful, if you could answer to my question, this will save time to search more in internet. I thank you in advance!
The way I like to see it, is an argument is true if it's a tautology. When I take the negation of the conclusion while keeping the rest the same, I am basically taking the negation of my argument. If all the branches at the end are dead, then I know the negation of my argument is a contradiction, hence it follows that the original proposition is always true. On the other hand, if there's even one branch that's open, it means the negation of the proposition can be true, ergo that the original proposition can be false.
Very good I like your videos. Is that a natural deduction as well or is that something else? The trees I got in my book is up side down and not as clear whats going on in them. They can prove stuff like (p->q) or (q->p) i do not get the hang on them. They seems to prove stuff without premisseses! But thanks again very helpful and well presented. Michael from Stockholm in Sweden
It’s crazy our professor makes fun of us when we don’t understand what we’re saying. Then he tells other students to teach other, a student said why aren’t we getting paid it was so hilarious cuz it was true
The tree rules are a visual depiction of what makes a formula true according to the standard truth table for each connective. For instance, to make p&q true on the table both p and q have to be true. Therefore the tree rule for & stacks p and q on top of each other, basically asserting that they are both true. But pvq is true if either p or q is true, thus the tree rule for the wedge is a branch, exploring both possibilities. In short the tree rules decompose formulas in the ways that would make the components true according the table. I hope that helps.
It took less than 20 minutes for me to understand what my logic professor has been expecting me to understand for over two weeks. Thank you so much!
Same here...
thank you so much! this is like finding water in a desert
It's 4 years later, but I have to agree. I got a problem that said "Show a resolution refutation proof tree" and had no idea what that was nor how to make it, and this was the best and only place that actually showed how to make one.
Too late to snap back: I guess, you mean "thank you so much! this is like finding *oasis*
" :D :D
totally agree!
I'm in a PhD program and I FINALLY understand truth trees. Thank you!
this is literally the only good explanation for proof trees that I found and its honestly far better than my university lecture, thank you so much and greetings from germany!!!
It's really fucked that most professors can't explain this shit to us.
4 years later and all the top videos on youtube are garbage except this one. Half of them have people filming their face more then doing any examples.
Wo studierst du ?
hahah, dass das video nach 5 Jahren immernoch hilfreich ist für Leute @@michaelsjourney777 in Heidelberg
Now I can use truth trees to verify the validity of the argument that this video was better than my university lecture. Thank you.
I'm in a symbolic logic class in university and really struggling, and this just explained things so much better than my professor or textbook
SAME!
WOW THIS VIDEO IS 11 YEARS OLD! SUPER HELPFUL, THANKS!!!
Thanks for this video. This is the only resource I have found on the internet that has enabled me to understand how truth trees work :)
2021 and you are still saving people. Make more videos please love the way you explain
Thank you so much taught a 4 weeks material in 20 minutes. Our prof has a tendency to teach assuming we all know these rules.
This is the 3rd video I watched and this one actually had me understanding truth trees at the end. Thank you!
I decided, for some ungodly reason, to take a six-week (online!) summer course for logic and I'm getting a bit overwhelmed. Your video was by FAR the most helpful and easy to follow. I just stumbled across it. You've got a like and subscribe for me.
I just hope you have other videos that will help with the rest of my classwork! Going to look right now! Thank you!
wow I think I learned everything in 19 mins instead of a 2 hour class . thank you
You smashed it mate! Surprisingly hard to find a good explanation of such a simple concept. Thanks!
This video was very well organized, and I like how you explained the reasoning behind many of the moves and anticipated many of the possible confusions in the video. Thank you for this.
Duuuude! Bless you soooooo much! I totally understood, crystal clear!
I've been struggling to understand this topic and then I found this video. Thank you very much!
im a philosophy student and i was struggling a lot with this topic, this video was extremely helpful! thank you so much :)
Thank you so much! Your video is a life saver, the explanation is clear, short and so much more understandable than any other explanation I looked into. Thank you!!
I'll personally be done with the course in 2 days but I found that there's a lack of instructions for truth tree tests of other sort. Like using a truth tree to test for truth-functional falsehood, tautologies, and truth-functional indeterminacy. Thanks for such a useful channel.
Excellent. Just the right amount of detail.
This was fantastic. Thank you for being clear, slow and concise!
Thanks dude, you explained this much better than my teacher.
This is a great video! Really helped me understand, amazing teaching! Thank you!
Finally a good and clear explanation...THANKS!
Great video, loved the way you explained everything!
Bless u for this!!! My teacher isn't too good at explaining :( u explained it great!
Amazing way of going through the concept. Super clear. Thank you!
Thank you for the video. It has been very helpful.
helping me study for my philosophy of logic final test, thanks a bunch buddy!
I'm so happy found this video :D
Just saved my Logic grade thanks mate!
thank you so much, very thorough and easy to understand!
I've my exams tomorrow. Thank you.
SLAY, great job!!! Now, even I understand:D ❤️
I agree with the other comments, this was very thorough crystal clear, and understandable, now just up to me to learn all the operations, haha... Thank you...
Wow, crystal clear explanation for truth trees! :D I'm just wondering why couldn't the ~D in the trunk of the tree close off the D in the branch? In the final step, that branch of the tree was eventually closed off anyway. :/
Because the ~D in the trunk is not by itself, it's part of a longer formula. Imagine if the ~D in the trunk had been part of the formula Bv~D; in that case the tree would had at least one open branch.
jellologic Thank you very much! You're very helpful! I wish all teachers/instructors were like you! :D
You sir are a life saver!
This video saves my ass in the upcoming exam, Thx!!!!!!
Watching this video to save myself from failing logic class
saved me for my quiz this monday!
Fantastic explanation, thank you.
I continue on listening to your video series. I have a general question. Are truth trees, truth tables and the proof method, explained in the videos from 1.1-3.10 substitutable methods for testing validity in propositional logic? I am listening to the playlist because concepts in logic (trees, tables, predicate logic, relations) are to some extend a building block in set theory, which on turn is necessary for measure theory, which is useful in integration in stochastic calculus, which in turn is necessary in financial valuation. I tried to skip lessons on logic, set and measure theory, but found it somewhat confounding, how stochastic calculus are applied in financial books without explanation in measure theory. I will be grateful, if you could answer to my question, this will save time to search more in internet. I thank you in advance!
Thank you, this clear my confusion
Finally a good explanation for how to do this
The way I like to see it, is an argument is true if it's a tautology. When I take the negation of the conclusion while keeping the rest the same, I am basically taking the negation of my argument. If all the branches at the end are dead, then I know the negation of my argument is a contradiction, hence it follows that the original proposition is always true. On the other hand, if there's even one branch that's open, it means the negation of the proposition can be true, ergo that the original proposition can be false.
You are the best, sir!!!!!!!!!!
Thanks man, great tutorial!
this is very clear thank you!
Very good I like your videos.
Is that a natural deduction as well or is that something else?
The trees I got in my book is up side down and not as clear whats going on in them.
They can prove stuff like (p->q) or (q->p) i do not get the hang on them.
They seems to prove stuff without premisseses!
But thanks again very helpful and well presented.
Michael from Stockholm in Sweden
Taught a semsters worth of work in 20 mins, amazing
I wish you were my actual logic teacher
"validity" here meaning specifically semantic entailment.
God bless thee
How the fuck did you just single-handedly save me from my test tomorrow
You saved me! Thanks so much!
Thank you sooooo much... my professor does not explain how it works friendly as you do...
i tried so many to understand it but couldnt, so thankkss alot :))
so so good. ty!
WOW such a clear explanation
super helpful. thanks
all teachers should teach like you, rather than trying to overcomplicate the subject as if we're spells
So helpful!
Sooooooo helpful!!!!!!!!!!
THANK YOU
Really helps a lot！Thanks！
Thanks!
Very good tutorial!
thanks!!!
Thanks Mate
amazing!!
Thank you!
TY TY TY
Do all logic teachers at university just suck? This video was very helpful.
Who developed truth trees? does anyone know?
Legend
It’s crazy our professor makes fun of us when we don’t understand what we’re saying. Then he tells other students to teach other, a student said why aren’t we getting paid it was so hilarious cuz it was true
life safer!
😘😘😘😘
i love you
can you teach us how those rules are made
The tree rules are a visual depiction of what makes a formula true according to the standard truth table for each connective. For instance, to make p&q true on the table both p and q have to be true. Therefore the tree rule for & stacks p and q on top of each other, basically asserting that they are both true. But pvq is true if either p or q is true, thus the tree rule for the wedge is a branch, exploring both possibilities. In short the tree rules decompose formulas in the ways that would make the components true according the table. I hope that helps.
i love you