hello everyone uh this is jodel again coming at you with the first actual lecture of the course hopefully by now you've already seen the previous thing i posted which was the syllabus if you haven't i would go watch that first because it sets things up a little bit better but this here is the first actual lecture lecture of the class where i'll be going into some of the material so i hope you're ready for that so what are we doing today i think we should start by going over a brief overview of what philosophy is so the course is listed as an leh course but it's being taught by the philosophy department at lehman college so i thought it would be helpful if you guys understood what philosophy was in general and then from there we can move on to what we're uh actually aiming for today which is an introduction to arguments um i'm sure you've all had arguments but in philosophy an argument is something very specific um it's a technical thing and as if you watch the previous video you'll also know that it's kind of the the one thing you need to know for this course right because if you've seen the previous video i spent maybe too much time talking about how i'm only going to be asking you to do one thing which is to apply concepts relating to arguments and in this lecture i will be introducing those concepts to you so it's kind of an important one and as always if by the end of it you're still a bit confused feel free to reach out to me okay so what is philosophy um it is a hard question to answer but you know we often say things like oh this person's philosophy is this or i have my own personal philosophy or so on and so forth but um what i mean by philosophy today is philosophy as what is now an academic discipline um so you know you're not going to come to this class and expect me to just tell you how to live your life and give you a guiding principle or philosophy what i'm what a philosophy class is is about studying the academic um results of the academic pursuit of philosophy and that might not make any sense to you yet but let's get into it so you might not philosophy is not something that's super popular in the general public but you may have heard some of these names socrates plato aristotle um just in terms of popular consciousness you may not know exactly who they are but you might have heard of their names and these are philosophers obviously um so these three are considered the i guess the main forefathers of western philosophical thought they are not the first philosophers but in terms of the tradition that we're going to be talking about in this class uh these are the three uh main guys so socrates was sort of a sort of a common figure in ancient greece he was uh executed for being annoying um you can read about that if you want on your own but plato was his student who supposedly wrote down all his teachings and then aristotle was plato student um who incidentally was the academic tutor of alexander the great who i'm sure you've definitely heard of um so those are the three sort of founders of western the western tradition of philosophy uh the next three guys i'm going to show you you've probably never heard of but they're kind of the kind of a big deal in terms of more recent philosophy that's rene descartes you may not have heard his name but you're definitely familiar with some of his creations if you've ever done math like at all beyond like a eighth grade level you're probably introduced to the cartesian plane which is where we plot points plot numbers on a sort of a plus sign and then plot points on that that was invented by rene descartes cartesian plane means from descartes so he was a mathematician in addition to being a philosopher so you may not have heard of him specifically but you're definitely using one of his creations if you've ever taken any uh math beyond high middle school david hume is another phosphor i won't get too much into him but he's one of my personal favorites i just thought you should know who he is he also sort of did a lot in sort of what knowledge would count his knowledge and he made a lot of interesting claims about the limits of what we could actually know um according to hume it's not very much um so that's pretty interesting then there's emmanuel kant who's someone we will be reading in this course he's probably one of the most important philosophers of the 19th century um he wrote about basically everything uh but for in the for this course he wrote a lot about he has his very own very specific moral theory that we'll be going into so i thought you should know who he is um so like i said you've probably never heard of these guys but uh you may have heard of the next three um cornell west he's uh he does a lot of like talk show strangely enough he does a lot of stroke shows and he does a lot of philosophy of race and philosophy of religion i think he's at the harvard theological seminary martha nassbaum she does a lot of work in feminism and a lot of work on ancient philosophy and angela davis i think you may have all heard of her by now she's like a black revolutionary was in the black panther party has a degree in philosophy surprisingly enough um you know so you may have heard of them but you know these three sets of people i've shown you're all very different um but what is it that they actually do you may have heard of some you may not have heard of others but what is it that a philosopher is interested in so one thing that philosophers do is define concepts so a question a philosopher might ask is what is it really like to be x where x is some object um for instance uh what does it really be to me what is it really to be a human being what is it really to know or something like that and you might think that's a pretty simple question just open up the dictionary but you know it's actually much harder than it looks so to demonstrate that um here's an opportunity for extra credit for those of you who are actually listening to the lecture i will post the discussion board in blackboard um and i'm going to ask you to sort of try to come up with a definition for a chair that's only a sentence or two and what makes a good definition a definition i want you to try to come up with a definition for chair that includes everything that we would consider a chair but excludes everything that we would not um it's harder than it looks so you might say a chair something with four legs and we sit down on it but there are a lot of things with four legs that we can sit down on would you count a bench as a chair would you count a bar stool as a chair um i'll leave that up to you to give it a shot and here's a bunch of examples would you when you make your own definition uh assuming that all of these things are not chairs some of them are chair-like some of them are other things that we used to sit down on but they're we wouldn't call them chairs so when you're making your own definition for extra credit uh try and see if your definition can include everything that is a chair but excludes some of these other chair-like objects you know a couch uh we don't really call that a chair but can your definition sort of illuminate as to why um and if you do this this is completely optional this i will add uh some points to your one of your midterms um and just as a reward for actually listening to the lecture okay so right so i said philosophers i try to answer what is it to be x questions um and this sort of tracks nicely with um sort of the main branches of philosophy so let's start with epistemology which is over here what is knowledge so if you're doing this kind of philosophy you're asking questions like what is it to really know how do we know anything how do we justify the things that we think we do know um uh you might say we all know that two plus two equals four but if i were to ask you how do we know two plus two equals four i doubt any of you could tell me much but you might say well that's what a mathematician would do fair enough but let me ask you this if i asked you how old you are you might say something like 25 i'm 25 for instance and then i'll and you say how old how do you know that you're 25 well i'll say something like well that's what my parents told me or i have a birth certificate or something like that and then a follow-up question would be something like how do you know your birth certificate is accurate how do you know your parents aren't lying to you and so on and such and it turns out a lot of things that we think are very obvious and very easily known when we're pushed to actually justify them um we're sort of put in a hard position because at a certain point we just have to just say well at some point i just got to trust what my mom says right or at some point i got to just trust with my birth certificate says and and if we're being honest in a sense we don't really know how who we are but we we kind of just act as if we do but a philosopher who's studying epistemology which is the study of knowledge would sort of try to come up with theories for figuring out how we know certain things what are the things that we can know um you might just say well we can't actually know anything that would make you a skeptic i'm sure you've heard that word but skepticism is a sort of its own thing in philosophy where you say uh it's where you sort of acknowledge that now knowledge you acknowledge that knowledge is impossible to attain it's a it's a view you could take in philosophy so these are the kinds of questions epistemologists sort of study another branch of philosophy is metaphysics it sounds very intimidating but it's simply the question of what exists or what things there are or the study of being or um so things like space time uh and so on and stuff we have to like think about it if i ask you what is time i think you'd have a hard time coming up with any coherent answers but that's what philosophers do or you know what what counts as an object that might be seen like a stupid question but you know we are we're often capable of saying something like that tree is by itself its own object but there's no real reason for us to draw the line at the tree in some sense we could make an object out of the tree and the grass that's within the one foot of it and say that that's one object or we could say the tree my left arm and the shoe you're wearing on your right foot right now is constant one object and you might say well that's a bad uh sort of classification because those are all very different things but if i were to ask you well what principle are you using to say that that's a bad object you would have a hard time coming up with one so these are kinds of questions that someone who's doing philosophy of metaphysics would do and then the remaining two of the things that we're going to be engaging with in this class uh the first one is value theory that's just another way of saying uh ethics or morality um obviously this class is studying moral theories and so on and we're cons we're concerned with questions like what is good what should we be doing so on and such and then the last uh main branch of philosophy is philosophy of logic which is what how do we know to properly reason how do we reason correctly so if i give you an argument how do i know that the argument you gave me is a good one right um we're not gonna be gonna be getting too much into this we're gonna just sort of dip our foot into it to get certain basic tools that allow us to evaluate arguments and then use that for the rest of the semester um a little logic goes a long way um as you'll soon see right so those are the main areas of philosophy and just think of philosophers of people trying to investigate certain questions that are um not exactly in the realm of science um we're asking different kinds of questions so you might say how uh how's philosophy different from science well so think about what scientists examined so if you're astronomer you're looking at celestial objects objects in space and how they came to be and so on and such if you're a geologist you're looking at the history of the earth as a as a as a structure and it's composition if you're a biologist you're looking at life uh how it came to be how it works how it reproduces these are questions that are empirical in nature and that sounds like a fancy term but it just means that these are questions that are about observable things um you know stars we know they're there because we can see them or we know that living things are there because we can well we are we are living things that we can interact with them um if you're a geologist the earth is there you can go you can touch it you're probably touching it in some sense right now these are things that are empirical in the sense that we can interact with them some way it doesn't have to be touched or sight you could smell any other stuff if it if we know it through our senses in any way that's an empirical object and science is primarily concerned with the gov with the rules that govern the empirical objects in the universe but um philosophers don't do that right we're concerned with concepts that's what we that's what we're concerned with we can't just uh so if you've done the chair exercise well when you try to do it and i tell you to come up with a definition for the chair you're not gonna look go outside your house start looking for the definition of a chair right what you're going to be doing is engaging with the concept of the chair you're going to be thinking about what makes a thing a chair uh you're going to sort of paint betraying your drawn sort of just your knowledge about what chairs do their purposes how we use them and so on and such but ultimately you're not gonna just look in the world and find oh this is the place where we store all the definitions about chairs and you might say well isn't that what a dictionary is um yes and no so a dictionary is sort of our best attempt at coming over definitions but how do those definitions get generated that we have to just sort of just think yeah we're working in the realm of concepts and we're not just you know there's no microscope to determine what the what it is to be a chair right that's a conceptual endeavor not an empirical one so that's how philosophy is different from science but what about religion is philosophy like that uh no so the differences are like this so in philosophy it seems like what i've from what i've said it seems like we're interested in asking particular questions and finding out their answers um it's more of a method of a way of going about things than it is a set of dogmas and codes so what it means to be part of religion is to accept certain beliefs of the religion and behave in certain ways that are in accordance with the religion but philosophy is not like that to be a philosopher you just have to be willing to ask a question and care about the term finding out the truth um we're not necessarily committed to any uh one thing being true um i think the biggest difference between philosophy and religion is that philosophy is open to revision anything that we believe now if a new breakthrough is made in philosophy we're completely willing to abandon what was said in the past um but obviously religions don't do that they're interested they think religions are about adherence to the received wisdom of the religious elders there's not much uh inquiry going on beyond that um so yeah that's the difference between the two so that's just a brief overview of what philosophers do i guess i could say something about what i'm interested personally and i do a lot of uh philosophy of race um so questions like are biological races real so for instance um it is common for us to think that our racial divisions like black white asian hispanic whatever are somehow biologically hard-coded this is not actually not something that's um you know obviously if you look at the science there isn't like a white gene or a black gene and so on and so there's an open question about whether um our notions of race that we use in our common speech is actually based on anything in science or whether it's socially constructed so on and such so that's one of the questions that one of my personal research is sort of uh concerned with um and as you can see it's not exactly a scientific question right so you know like i said i may use science to support my claims and say well there isn't a black gene or there isn't a white gene but then it's a further sort of conceptual question of whether that uh that whether that means the race is do or do not exist so that's like a sort of example of how philosophy is different from science because you know science gives us data but how we organize and sort of um synthesize that data into new information that's that's conceptual work and that that's what philosophers do so i think i hope that's been helpful for figuring out what philosophy in general is um but for the case of in the case of this course like i said if you've done if you've watched the other video we're concerned with morality and concepts relating to morality and you know i'm not gonna and the purpose of this class is not for me to just tell you hey this is what's moral to do and just do what i say the purpose of this class is to examine different moral theories and determine whether the arguments that are supposed to get you to come to believe in those moral theories are good ones or not all right but i just use the word there argument um what is an argument and that's where the next part of our lecture is going to be about so arguments um it's another term that we use in our common speech all the time it doesn't mean two people yelling at each other uh in philosophy an argument is something very specific and and i and that by by the end of this presentation i hope you have an understanding of one what an argument is to what a valid argument is and three what a sound argument is okay okay so it might be helpful to figure out what an argument is not before we figure out what it is so the closest thing someone might give that sounds like an argument that isn't is an explanation so an explanation sort of is something we give to someone to explain why something that we already believe to be true is happening so here's a simple example we're trying to explain why the kitchen was so hot this morning when we woke up and then as in way of explanation i'll say something like the oven was left on overnight and when you leave the oven on the kitchen gets hotter and this explains why the kitchen was hot this morning right so that's an explanation now what's the difference between that and an argument is an argument gives reasons in the form of premises that if true would support the conclusion being drawn so what that means is that when i'm giving an argument to someone um there's a conclusion that i'm trying to argue in favor of right and the way i do that is by making by giving reasons or premises is what we call them that when when taken together gives support for the conclusion i'm arguing for so for example here's an argument with premises premise one all men are mortal okay this just means that if you're a human being you're gonna die one day premise two socrates the guy from earlier is a man that's uh pretty uh self-evident conclusion therefore socrates is bortle what makes this an argument is that i'm trying to get you to agree to the conclusion that socrates is immortal and how do i do that i give premises that support that conclusion so i say look all men are mortal right and if socrates is a man he's gonna be mortal just like every other man and then therefore that gives you reasons to agree accept the conclusion that socrates is mortal right so that's a a brief um sort of explanation of the difference between an explanation an argument um and like i said before an argument is not just two people yelling at each other in philosophy and argument is a series of sentences that are trying to uh get the reader to accept a particular conclusion okay and these sentences are premises that all serve to flow to the conclusion all right so what are arguments made of so i just said that arguments are a series of sentences but not if there are differences between the sentences in an argument so an argument has two components premises and conclusions so a premise is just a sentence that makes a claim about the world so if i say something like the earth is round um that can be used to support an argument uh it hurts to touch fire dogs are cute these are statements about the world and i can sort of put them together i can put statements about the world together to sort of get you to accept the furthest uh statement about the world so what makes a good argument a good argument is that the premises remember these are just the statements about the world the premises that i'm putting forward in the argument actually come together to support the conclusion being argued for and of course the conclusion is just the claim that i'm trying to our support so here's some more examples premise one the t-shirt is black premise two jodel likes to wear black clothes conclusion jodel would like wearing the t-shirt um notice the premises uh they're making claims about the world maybe what kind of t-shirt it is what color it is and something about jodel that he likes to wear them obviously these sentences taken together went true would sort of support the conclusion that jodel would like wearing the t-shirt here's another one today is monday premise two my mother does not work on mondays conclusion my mother will not be work be at work today right so if today's monday uh my mother does not work on mondays uh these two premises when taken together supports conclusion that my mother will not be at work today and here's an interesting one all green things are made of cheese premise two the moon is green conclusion the moon is made of cheese so you might say those promises are absurd obviously the moon isn't green and all green things are made of cheese but what we're looking at here is the form of an argument right the premises uh sort of if they were to sort of do support to conclusion we have to imagine if all green things were made of cheese and imagine if the moon was green if those two premises were true that conclusion that the moon is made of cheese would also have to be true and that's what makes it an argument the premises support the conclusion okay so some key terms so far one what is an argument an argument is a series of sentences that when together support a particular conclusion what is an argument made of an argument is made out of premises which are sentences that make a claim about the world and conclusions which is another claim about the world that we're trying to support with the premises okay so are all arguments just as good obviously not but um is it it's a technical term between what makes an argument good or bad we don't say good argument or bad argument uh we say invalid argument for a bad argument and valid argument for a good argument um it's it's you should be careful here because in common speech we see oh that argument sounds valid all the time to mean that it's a good argument which is not necessarily true as we'll see later valid validity in our class means something very specific um so this is this is the part of the the only thing that's going to be difficult in the class understanding the difference between invalidity and validity so uh i would sort of go over these slides a couple times if you're still having problems with it so an invalid argument is an argument where if we imagine the premise to be true it would not necessarily mean that the conclusion is true so what i'm saying here is that there are arguments so there's something that meets the criteria of being an argument but the conclusion doesn't actually is not actually supported by the premises so for example if i say premise one all goats are mammals uh premise two horses are larger than mosquitoes conclusion dogs are better than cats um that's clearly a not a good argument why because the premises have nothing to do with the conclusion um so they're not really supporting conclusions so that would mean that the argument is invalid if someone were trying was trying to convince you that dogs are better than cats and they said something about goats and something about horses that clearly doesn't support the conclusion that dogs are brighter than cats so we call this kind of argument invalid but it's notice here that both the premises are actually true right so all goats are mammals and horses are larger than mosquitoes so the trick here is to recognize that being invalid does not necessarily mean the same thing as being false okay right you can have a invalid argument with true premises all right that's an important thing to recognize because this is how people get tripped up so unlike um right so even if the premise one and premise two are true it does not support the conclusion being true and that's what makes the argument invalid in essence okay so then we have the valid arguments right an argument is valid where if we imagine the premises were true it must be the case that the conclusion is true and by that i literally just mean that the conclusions is supported by the premises right so if i'm going back to the earlier example all green things are made of cheese premise two the moon is green the moon is made of cheese you'll say wait those promises are false but remember validity is not about whether the premises are true or false notice here it says if we imagine the premises to be true so you have to put on a sort of hypothetical cap and say look let's imagine that all green things are made of cheese and then say let's imagine that the moon is green is would the moon be made of cheese in that world and the answer is yes um it's a hypothetic uh so validity is a property of whole arguments and it's completely unrelated to whether the premises are actually true or not uh when you're testing validity you just make sure that the premises are you imagine that the premises are true and then see if the conclusion is supported by those premises right so um another and one last thing to remember about between in being invalid and valid is that validity and invalidity apply to arguments as a whole [Music] and not to individual premises or conclusions right so the argument is the set of all the sentences and but that set of sentences can be valid or invalid um not the individual premises so one thing i see students often make mistakes about is that they'll say they'll say something like oh all green all green things are made of cheese we'll say oh that premise is false and that means that the premise is invalid that's a mistake right because as i've just demonstrated premises can be false but still be valid for an argument okay so make sure you're applying the concepts correctly invalidity and validity are only applicable to arguments which is the set of all the sentences they are not applicable to individual premises and conclusions um this is probably the one thing that trips up students the most okay so remember valid arguments can have false premises because validity is not about uh true truth or falsity it's about whether the conclusion is supported by the premises whether those premises are true or not okay and you might say who cares about an argument that's valid if it has false premises and you're right uh what we really care about are arguments with that are valid with true premises and what do we call these arguments we call these arguments sound so soundness is a property of arguments that's what we really want right so when we're making an argument to someone else we want the argument that we're making to be sound and what is it to be sound a sound argument just is a valid argument whose premises are actually true in our world okay so let's go let's go over that again a sound argument is a valid argument and remember a valid argument is an argument where if the premises were true the conclusion has to be true okay and then to get the soundness from a valid argument the premises have to actually be true in our world and remember we care when we're trying to prove things to other people we care about our world obviously so this is what we care about in in this basically all of our interactions we care about sound arguments and i'm sure you've heard the word sound before and just like you heard the word valid before but they mean very different things as you can see right because remember a valid argument doesn't have to have true premises but by definition a sound argument must have true premises and this is sort of like the gold standard of an argument when you're making an argument to someone else what you want is to make a sound argument okay so let's look at the example here all men are mortal premise two socrates is a man therefore socrates is mortal this argument is valid why because if we imagine premise one and premise two were true if we imagine that all men are mortal and we imagine that socrates is a man in that hypothetical world yeah it would be true that socrates is mortal but now to test for soundness we have to examine whether the premises are true or not and in our world it is the case that all men are mortal i'm assuming vampires don't exist um and two it was this case that socrates is a man therefore the argument is sound why because it's valid if the premises were true it would support the conclusion and it's sound why because it's a valid argument with true premises that's what makes um an argument sound so let's go through these concepts real quick again i'll go back to the slides so once you know what an argument is which is a series of sentences that are trying to support a conclusion from there and we know that arguments made of premises that support the conclusion and there are two kinds of arguments while there are three kinds excuse me they are the what we're calling the bad arguments these are the arguments where the the premises do not support the conclusion these arguments are invalid we call the good good arguments valid by that we just mean that if the premises were true the conclusion would have to be true and then we have the best argument which is the one we actually care about making which are the sound arguments these are valid arguments that means the premises support the conclusion [Music] and the premises are actually true in our world right so those are the three main concepts and i promise you if you understand these concepts this class will be very easy for you because that's all i'm going to be uh testing you on throughout the midterms and the assignments okay um just to go through some examples so here on the left we have the list just some invalid arguments and i've put whether the premises are true or false so um here's an invalid argument all green things are made of cheese the moon is red the boon is made of cheese um so these premises are actually false but remember if we're testing validity we don't care about that we have to imagine let's assume the premises are true premise one all green things are made of cheese let's assume that that's true true and let's assume that the moon is red if we assume those things does it then follow that the moon is made of cheese not necessarily okay the premises in this case do not support the conclusion okay here's another example it always rains on wednesday premise two tomorrow is thursday conclusion it rained yesterday right so premise one um it always means on wednesday is false and tomorrow's thursday is also false because today is saturday but that's irrelevant so let's assume that it always rains on a wednesday when we're testing validity let's assume that tomorrow is thursday if those two sentences are true would it then follow that it rained yesterday no right these premises do not support the conclusion of this argument therefore we say that it is invalid okay um so those were invalid arguments that had false premises but remember invalid arguments can also have true premises so here's an example of that over here um premise one humans have teeth that's obviously true premise two mice have teeth that's also true conclusion cats have teeth now notice there despite the fact that both the premises are actually true and even the conclusion in this case also happens to be true as an argument it's invalid because these two premises do not support the conclusion that cats have teeth right why because the premises say nothing about cats and implied nothing about whether they have teeth or not um another way to put it is humans having teeth and can humans can have teeth mice can have teeth but that has no necessary connection between whether or not cats have teeth like i said like i keep saying these premises do not support the conclusion here's another example of a invalid argument with true premise premises clouds are made of water vapor uh that's true boiling water produces water vapor that's also true water vapor is transparent okay um water vapor does in fact happen to be transparent and by that i just mean you can't really see it unless you know it's sort of refracted of a opaque background and but the premises are true and why is it invalid still because even if those first two premises are true the conclusion does not necessarily follow from that um so yeah so it's important to recognize that invalid arguments can have true premises so this goes back to the earlier point i made validity and invalidity have nothing to do with whether the premises are actually true it's about whether the conclusion is in fact supported by the premises if they were true um okay so here's some valid arguments um all green things are made of cheese this is the same example from before the moon is green the moon is made of cheese ah but these premises are false but if we imagine the premises were true it would then mean that the moon is made of cheese here's another one chickens can fly uh flying birds always weigh 10 pounds chickens always weigh 10 pounds so that's a valid argument but notice the premises are false once again highlighting the fact that validity has nothing to do with the premise whether or not the premises are actually true or not we imagine if the premises were true we imagine a world where chickens could indeed fly and we imagine a world that where flying birds always weigh 10 pounds and in such a hypothetical world those premises do support the conclusion that the chicken always wait chickens always weigh 10 pounds because all birds weigh 10 pounds flying birds weigh 10 pounds in this world okay and now let's go into sound arguments remember by definition a sound argument will all will have to be a valid argument okay so when testing the soundness of an argument you have to first test the validity of the argument right so let's do that here with the first example so we're testing validity first premise one all humans are mammals okay premise two you are a human so um we're testing validity so we imagine that these premises are true if all humans are mammals and you are a human being then the conclusion is obviously going to be supported by those two premises which says that you are a mammal so we at least now know that the argument is valid but now um how do we test if it's sound that's the easy part right we just say are all humans mammals yes just open up a text taxonomical work it'll tell you humans are mammals um are you a human i would imagine you are if you're taking this class so that's true therefore this argument is valid with true premises which makes it sound okay um let's look at the last example a cinderblock weighs 38 pounds we're testing validity first remember a cinder block weighs a 38 pounds a gallon of liquid water is eight pounds therefore a gallon of water lace weighs less than the cinder block okay so we test validity if a cinder block does weigh 38 pounds and if a gallon of water is eight pounds then it would make sense to say that a gallon of water weighs less than the cinder block so we know the argument is valid but now we want to test whether it's sound does the cinder block weigh 38 pounds um yes it does i just googled it to make sure um does the gal in the water weigh 8 pounds yes it does i also just google that and assuming google is correct that means that these premises are true so what we have here is a valid argument with true premises okay and that's what it makes well that's what makes a sound argument uh so just a couple of things before we finish off um the hardest part is identifying whether the argument is valid or not right as i've said before validity is a property of the whole argument that all of the statements combined not the individual premises as i've been trying to demonstrate here to you guys is that whether the premises are actually false or whether they're actually true has no bearing on whether the argument is valid or not right what validity is concerned with was whether or not the premises if they were true whether and or not they are true if they were true whether they would support the conclusion okay and once you determine whether an argument is valid it's just a simple matter of identifying whether the premises are true or not all right so um so some key terms to take away from this lecture you have to know what an argument is you have to know what an invalid argument is you have to know what a valid argument is and you have to know what a sound argument is right it sounds like a lot but i will be posting some worksheets that will be your first assignment that will basically hammer in these concepts to you okay and if you know what these four things are the class will be very easy because that's all the logic that we're going to be doing just knowing whether an argument is valid invalid or sound that's all that we're that's the hardest thing we're going to be doing in the class and if you can pick up these things the rest will be easy and the rest of the class will just be a matter of applying these concepts to various moral arguments that we're going to be examining later on in the semester um so uh thank you for watching so remember i put i'm going to be posting the extra credit blackboard assignment which where you're supposed to come up with a definition for a chair that includes everything that we would consider a chair but excludes everything that we would not consider mature that includes things like bar stools and couches and park benches and the first assignment will be i'm going to upload a series of worksheets that if you um i won't be grading these but if you do them i will i will give you some points on your midterm as well so i guess the first assignment will also be extra credit um because why not but i highly recommend you do them if you're still a bit fuzzy about uh what the difference between validity and inability is and how you test for soundness and also you can always just go on youtube and type in validity and soundness and i'm sure you'll find uh even more videos explaining the concepts to you and uh and as always if you're confused about something we can have a zoom meeting meet up one-on-one and we can go through it again and like i said if you get these concepts the rest of the class will be a breeze because that's this is the hardest thing i'm going to be asking you to pay attention to okay guys thanks for watching and i'll you'll hear me again hear from me again next week thank you