 OK, so the topic of today is actually the scientific method. And I'm going to do my best to walk you through the basics. I promised you that we would equip you with a toolkit that you could use to detect nonsense, fraud, scams, lies. Science is a very important way of knowing, which I'll emphasize later. And the method is the basis of all good science that's done. So before I begin, I have to start with something philosophical. A lot of people like to attack science, claiming that it's just another philosophy and that you can ignore it because all philosophies are equal. And I'll come to that point in a bit. And it is true that science in part contains philosophy, but it is more than philosophy. It supersedes the philosophy on which it's built. I mean, you can think of philosophy as bricks. Science is a cathedral built out of those bricks. It has many other parts that go into it. It is not only philosophy, but there is a philosophical underpinning. And if you can't accept that philosophical underpinning, then you can't do science. Because science is fundamentally based on you and me and everybody else being able to at least agree that there's a common thing that we can all come to agreement on. And so science is built on something called objectivism. So let me sketch that out a little bit. Objectivism basically states that there is an objective reality on which we can all agree. It's the same for everyone. For you, for you, for you, for you folks back there in the back, all the same. Reality is the same for all of us. I'm going to get these out and they can look at them. Yeah, we have an attendance quiz coming out. Just attendance today, not reading. So you can fill this out at your leisure as we go. But here we get them at the end of the class. Right, yeah. Hand them back in at the end of class, OK? Or what I recommend doing is when you're done with it, pass it down the road to the person at the beginning of the row. And we'll collect the pile from the person at the beginning of the rise, OK? All right, so back to objectivism. So there's an objective reality that's the same for everyone. And there exist unchanging laws by which the universe works, operates, OK? So those laws may be simple, but out of that very complex phenomena can occur. And those laws can be discovered. That is, they're there for us to find. They're not to be invented. They are regular laws that anybody could agree on if they assess reality, if they assess the natural world, OK? That's objectivism. And that's the basis of science. Science operates on the assumption that we can all apply the same framework and come to the same answer. And the only way that that can be true is if we believe that there is actually an objective reality that we can all agree on, all right? So objectivism is a belief. It's a belief. You have to believe in objectivism to do science. Otherwise, you can't make any progress. So it is the one thing in science that is purely a belief. I can't prove it to you. I can't prove to you that there is an objective reality that we can all agree on. But what I can do is I can justify that this philosophy of objectivism is a good philosophy, OK? It has enabled us by discovering many of the laws of physics. We know there are laws we haven't figured out yet, but we've discovered a whole lot of them in hundreds of years of searching. And based on those laws, we have done astounding things with engineering. So here's a beautiful skyline, an airport in the front, and then really a pinnacle of modern engineering, which is the aircraft. And engineering, yes, engineers design and build all of this stuff, but the operating principles on which they can improve designs, on which they can make better products, are based in the laws of physics. And so the laws of physics allow progress to be made through engineering by advancing engineering and making safer structures, better structures, stronger structures, faster structures, et cetera. So objectivism is practical. It lets you make progress and lets you do things like this. It lets us send people to the moon to walk on the surface of the moon to escape the confines of the sea of air that we're normally trapped in. When you think about it, humans are confined to a very small portion of the Earth, or confined to its surface. And sometimes we go under water, but not most of us don't go under water for long periods of time. We certainly can't breathe water. We're trapped in our atmosphere. And so it's really quite astounding, because through science, through the scientific method, we have developed means to breathe air under water and breathe air in the vacuum of space, where there is no air. We have sent extensions of ourselves, mechanical probes, to the surface of Mars to teach us about the geology and the history of Mars in the hopes of maybe understanding whether or not life is there or was there at one point. So we, as living creatures, have sent probes on our behalf to look for other living creatures. This has all been made possible by objectivism. Because if the laws were different on Mars, none of this would work. If gravity didn't work the same way on Mars, if chemistry and biology didn't work the same way on Mars, if those fundamental laws were different, then this would never have succeeded. Modern telecommunications, by the way, protip. Not a good way to use your iPhone. Just going to say that out loud. Modern telecommunication, the iPhone that this infant has grasped and is now sucking on. I watch my nephews and nieces do this too. That's all possible because of quantum physics, general relativity, the theory of relativity invented by Einstein, which explains space and time and gravity. So he uncovered the laws of space and time and gravity and energy and mass and all that stuff, united them through relativity and quantum mechanics. These are beautiful laws. They seem esoteric. But actually, your iPhone can't work without them. The GPS system that's built into your car, your iPhone, your running bracelet, whatever. That GPS system uses signals sent to satellites in orbit around the Earth. And those signals, if we didn't know that gravity affected them, would never sync up. And every day, you'd be 11 kilometers wrong, more, than you were the day before. And we only understand that effect because of understanding the basic laws of physics. Objectivism makes progress. It makes our lives better. It has improved the human condition. The laws of biology, the laws of chemistry, these things unite and they give us a picture of the diversity of life on Earth. Why is life so diverse? Why are there so many forms? Here you have a human being briefly escaping the confines of the air, ocean that were stuck in breathing most of the time, to swim with these beautiful whales. Whales, which are themselves air breathers that spend most of their lives underwater. They were once their distant, distant, distant cousins once walked on the surface of the Earth but returned to the ocean. They still have vestigial hip bones in the backs of their bodies. That are very like ours. And sharks don't have those because sharks came from very distant cousins that never walked on land. They didn't need to walk. They didn't need hip bones. Hippos are actually a closer relative of whales than whales are a relative of sharks. That astounding fact is only explained by biology and by chemistry and by all the things that make the diversity of life possible. Objectivism is practical. It's useful. That understanding has enabled modern medicine. It has more than double the lifespan of the average human being in just two centuries. Through the application of chemistry and biology, we now have a very good understanding of what causes disease. What is it that makes us respond the same to certain chemicals, differently to certain chemicals or genetics? Objectivism is useful. So I can't prove to you that objectivism is correct. All I can tell you is that it has improved the human conditions in ways that no other school of thought has ever managed. So it is practically useful. And that's why I believe in it. Now there is another way of thinking. There is relativism. So objectivism, there is an objective reality, the same reality with laws that we can all discover and we all agree on. Relativism takes the other approach. So there are a couple of schools of relativism. There is solipsism. Solipsism is the belief that everyone, you and you and you folks back there, you all create your own reality. That maybe you have your own private law of gravity, your own private mathematical rules, your own private laws of chemistry and biology. Now it doesn't usually go that far. But when you believe that all things are relative, that you create reality as you go along, you create reality, there's no reason you two should ever agree on the laws of nature. So how will you ever make progress with that belief? Because everything's different for you than for you. So you might be able to walk on the moon, but because you have a different law of gravity, you're going to miss the moon and go flying off in the space. That's a problem. That doesn't let you really get anywhere. So this approach doesn't really produce any useful results. If you run it to its conclusion, if you tried to build a scientific framework off of relativism, it wouldn't work. Because you have different rules for everybody. So if your own private reality is different, you have a problem. The solipsistic approach really fundamentally yields nothing useful. You can go ahead and believe in it, fine. But if you're going to try to make progress with it by applying it as a rule, you're going to be in real trouble real fast. It doesn't improve the human condition. Now, a couple of easy things to remember. If you think you're creating your own reality right now, flap your arms and fly. If the law of gravity is different from you, you should be taking off. Yeah, come on, you can try harder. Well, maybe the laws of fluid motion are also different. Yes, exactly. So you're not generating any lift. Yeah, OK, and that's getting into a construct. So we'll talk about that in a bit. That's great, thanks for interested in getting that. Will yourself an A in this class, OK? You have to work, all right? So I like this cartoon just because it reminds me why Dilbert coming off as kind of a jerk sometimes isn't married. So I've had this conversation before, OK? I collect crystals, Dilbert thinks, uh-oh. I don't know of any scientific evidence that they can heal. That's good. But it's my point of view that they do, OK? And then, of course, he says out loud, which you shouldn't. When did ignorance become a point of view, all right? So this relativistic approach can come off as, well, I mean, there's no absolutely no reproducible evidence that x causes y. But I believe that x causes y, OK? Because it's my reality. OK, and we'll talk about the consequences of that. For instance, when we talk about alternative medicine and things like that, OK? That has dangerous consequences. Now, there's another form of relativism, new age or post-modern thinking that goes under a couple of names. And the tentative of this belief is that all points of view are equally valid, OK? This comes off in the popular media's A. Everybody's entitled to their opinion. There's two sides to every issue. This person over here has equal weight to that person over there, OK? That's nice and touchy-feely, but this is a class about the scientific method. And of course, that class is based on the idea that there's an objective reality whose laws can be discovered through experimentation that we can all agree on. And that means that there are right answers and there are many, many, many, many, many wrong ones, OK? So you'll find that Professor Cotton and I are not among a group of people because we really try to live our lives as scientists, OK? Sure, we have non-sciency beliefs that happens, right? But when we try to really come to a decision about things, we use the scientific method as best we can if it's applicable and it has limits. Now, you might think that because we're not touchy-feely about all this, your opinion is just as valid as anybody else is about a scientific issue, OK? I'm talking about a scientific issue, an issue about the natural world and reality, OK? You might feel we're biased or one-sided because we ignore some points of view. But in science, you're really going to encounter the disturbing fact that if your point of view runs counter to the weight of the evidence, it's considered wrong. It's not going to produce any useful results because it doesn't comply with reality, OK? If we kept all the bad ideas that had ever existed, we would be very confused as a species right now. But actually, the human mind is very good at sorting out what works and what doesn't. But it can be fooled. And this class is about teaching you the toolkit that lets you, especially, tamp down your emotional response and think critically and creatively about a claim, an issue, a question, a study, all that stuff, OK? Especially as it bears on reality the natural world. Scientific issues are not decided by votes. Yeah, scientific issues aren't. Science is not a democracy, OK? Now, there are some interesting treatises out there on how science and democracy may go hand in hand, but those are political science works, OK? Science is not a democracy. We don't vote on the laws of physics. That would be a disaster. We rely on the method, which I'll explain in a moment, to come to an understanding of what the best answer is, OK? Now, the right answer, the one that's absolutely correct, you may never find, but you will find the best one given all the evidence you've collected so far. And that's what science strives to do, is get to a better and better and better answer that we think would approximate reality, OK? The truth, if you will. All right, now that means that our view of the universe can actually change as science continues to operate and uncovers more of the secrets of the cosmos. But that change of view will be driven by the evidence and its reliability that's collected by the process, and not by whether I feel like that can't be right or my parent told me that's not true, OK? You're going to start learning about things like logical fallacies from B&K, which you're reading now, Brown and Keely, OK? And you're going to find that a lot of the things we take as good evidence are, in fact, BS because there are arguments from authority, their misdirection, their attacks on a person, but not their idea. These are all tricks that people use to get to your heart and avoid your head. And we're going to try to give you a toolkit that starts here and tamps this down just a little bit. It's impossible to take a motion out of the human equation, OK? But we can give you a framework, and I don't know why, but I always think about the terrible movie Starship Troopers when I think about this. Was I lucky to miss that? You were lucky to miss that, because the book is phenomenal. But as a political science and science fiction work, the book is an incredible exploration of an alternative political society. But the movie is awful. It's campy. It was great. I saw it for free in college. It was awesome. And there's this one scene where you have all these space marines puking on themselves as they're about to land on a planet. And the sergeant says, remember your training. It will save you. And actually, they all get massacred. But that's beside the point, OK? Remember your training. It will save you. OK? Now, relativism has an interesting logical problem, which is that it actually just proves itself. Now, if you're a logic, wonk, you'll enjoy this, OK? But if you're not, maybe you'll start liking logic because of this. So this is from Schick and Vaughn, which is a book we have routinely used for the course, but we're not using it this semester. But if you take a look at it and flip to page 325, I put emphasis in where I think things are key here. They have a pretty condensed version of this. Basically, to say that everything is relative, I have to say that you create reality, you create reality, you create reality, is basically to say that there are no universal generalizations. That is, there's no thing that's true everywhere at all times for everyone and every point in space. These are unrestricted universal generalizations, like the law of gravity. The law of gravity would be an unrestricted universal generalization. We will be based on evidence it's true everywhere. That's not allowed in relativism. The statement that no unrestricted universal generalizations are true is itself an unrestricted universal generalization. That is, there is no thing in the cosmos that is the same. That's an unrestricted universal generalization. And so for relativism in any of its forms is true, it's false. So as a result, they can't be true. So that's just, if you like logic, that's sort of a fun little thing you can play with. So now let's talk about the scientific method, which is an awesome way of knowing it. I'm bled it. Yeah, but it works. It's like medicine, it might taste bad sometimes, but damn if it don't work. All right, so what is the scientific method? Here's the simple answer. If you remember any one thing about the scientific method, this is what it boils down to. It's a reliable and reproducible way of ensuring that you do not fool yourself and that you are not fooled by others. You do not fool yourself and you are not fooled by others. And as you're going to see in this class, you're going to be fooled a lot. People will try to fool you all the time. Who's the easiest person to fool? Yeah, who's the easiest person to fool? Yourself. Yourself, yeah. And I have to remember that constantly. So you should, too. Looking for little bumps that look like kigs. Yeah, yeah, I search for particles that we don't know if they exist or not. And so we have to be very careful when we're looking at our data not to fool ourselves into thinking that some little statistical fluctuation that might just be an accident of a flu is a discovery. And in my community, we're really over cautious. We need to have two experiments. And we need to achieve a certain threshold of confidence in the data. And they both have to be independent. We don't talk to each other. You'll see this is all part of the scientific method, but it's a way of building in mechanisms to prevent yourself from being fooled. Because physics, like every other discipline, has fooled itself in the past. Clever people believe wrong things. And you have to be very careful about that. Here are the nuts and bolts of the scientific method. Step one, make an observation and a description of a phenomenon. Step two, formulate a hypothesis to explain the phenomenon. Hypothesis takes the form of a causal mechanism or a mathematical relationship. This requires creative thinking. We'll go more into a hypothesis building next time, but this is the creative part of science. The mechanism of explanation for the phenomenon must be plausible. OK? We'll get into that, too. New Greenblins. No invisible fairies that can't be detected because they give off no heat and light and things like that. Use of a hypothesis to predict the existence of other phenomena or to predict quantitatively the results of no observation. So in step three, you take your causal explanation and you say, if this is true, if this is an explanation of the phenomenon from step one, then I propose a test to verify that. So observe, try to explain, state the consequences of the explanation, and then finally, step four, perform an experimental test or tests of that prediction by several independent people, groups, whatever, and properly controlled and performed experiments. This is dense. And we are going to hit on every piece of this as we go through the class, but we're going to start by demonstrating the framework to you, OK? So you can see how it works practically speaking, all right? So again, step one, observe. Observe a phenomenon. When I flip the switch, the lights go off, OK? That's a phenomenon. When I flip the switch again, they come back on. Now, that's an observation, OK? The next thing you'd have to do then is if you wanted to explain that is to formulate a plausible causal mechanism by which that happens, OK? So there are gnomes in the wall who are very quiet. They're very shy. If you open up the wall to find them, you won't see them. You can't also, by the way, even if you could see them, they're invisible. And they give off no heat, light, or radiation. Is that a plausible explanation? Can we all agree on that? Do they give up? Do they have gravity? No. No, yeah. Well, we don't know if that exists either, I don't really know what it is. So that's a non-plausible explanation. It's kind of relativistic, because I state that there are these gnomes that you can't see. Well, how do I know that? How the heck do I know there are invisible gnomes that you can't see? I have magic eyes, right? All right, now we're into fantasy land, OK? There must be something that the switch controls that when you flip the switch one way, it causes light, and if you touch the bulb, heat to be given off by the bulb. And when you flip it the other way, it stops the flow of that thing, OK? So all right, great. So the use of the hypothesis now is to predict the existence of other phenomena. If I pop the wall plate off, and I look my fingers, and I become the switch, I predict that I will feel a force. I've done this. I don't recommend it. It's not fun. OK, that would be a possibility, OK? So now I pop the wall plate off, and I do it. I commit. I get some funding from the department chair in the form of life insurance, and then I take my fingers and I shove them into the socket, and I see what happens. OK, that's an experiment, OK? It can be very simple. It can be very simple, all right? So you make a hypothesis like this. Let's say I do that. Let's say I take my fingers, and I lift them, and I shove them into the switch. You have to pull the wall plate off, OK? It passes the test. I drop on the floor, screaming, right? Now what does that imply about the hypothesis? Well, I haven't actually proved that the hypothesis is correct, that it's the true explanation of the phenomenon I observed. All I can say is, after I scrape myself off the floor and stop crying, well, I have more confidence in my hypothesis now, or probably more like, I have more confidence in my hypothesis, and I'll never do that again. Probably something more like that, OK? It might still be wrong. It might be that the gnomes have hammers, and that if anyone puts their fingers in the wall, they snap them, and that's what I felt, OK? Or they reach out, and they grab my heart, and they squeeze. All right, indeed, you can never actually prove the hypothesis completely correct. All you can ever do is say that your hypothesis passes test after test after test. You can be more certain of the hypothesis, OK? And a result that contradicts the hypothesis, if I do stick my fingers in there, all right, and I don't experience any force of any kind, well, that might be evidence against my hypothesis. So it might be wrong. So you can prove a hypothesis wrong by it makes a very definite prediction. So for instance, what if I then say, OK, well, I believe that if I take a fan, and I stick it in the switch, the fan will start spinning, and the fan doesn't start spinning. So then there's something special about the light bulbs. OK, that might disprove my original hypothesis, in which case I have to toss it and start over. I need a new hypothesis. So hypotheses, really the key thing that makes a hypothesis plausible, is that it can be disproven. That there is a test that exists, at least one and probably more than one, where if you find out that the hypothesis fails the test, the hypothesis is wrong. And it either needs to be modified or you need to start over, OK? Now, hypotheses that are not disprovable are not in the purview of science, OK? And this already sort of helps you start to understand why there really isn't a tension, for instance, between science and theology or religion, OK? Because theology and religion are about things that you believe in without requiring evidence. And science is about things you believe in because there is evidence for them, all right? Your faith, your religion, your theology should never be really based on things that can be disproven. That's not really faith, OK? It's dangerous. It's dangerous, in fact. Yeah, you want to be careful with that stuff, OK? And science should never be based on things that can't be disproven. That's the difference. And so that's why those two things are really not in conflict with one another. It's only people that bring them into conflict because you can easily confuse these two realms, all right? So this is the key. It's really the core element of science is causal explanations for phenomena that are plausible because they can be disproven by a test. They might withstand test after test after test after test, but they could be disproven at any moment by the next test. And then that disprove has to be verified and all that stuff. But that's a good hypothesis. So that's what I just said, basically, OK? Good hypothesis can be disproven and it can withstand tests, but it can never be proven absolutely true. You can just gain more confidence in it. OK, so let's do a class poll. So for those of you who were in here last time, you just got these flashcards. Hit the flashcards out, all right? The way these class polls work is I want them private. I don't want you to feel peer pressure. I don't want you to feel like your friends are influencing you or that random stranger that's crushed next to you in this tiny classroom is doing anything to change your answer. So we have a poll, A, B, and C. We have three cards. A, B, and C, white, blue, and pink. And what I want you to do is just put the cards down, shuffle them until you get to the answer you think is the right one. And then all you have to do, for instance, is take the card and cup it and hold it up under your chin like this. And that will show me your answer. It will show Professor Cotton your answer. So here's the poll. What is a theory in the scientific sense? A, akin to a hypothesis, a plausible explanation for an observed phenomenon that needs to be tested. B, more akin to a law, a well-tested explanation that includes facts, laws, and tested hypotheses. C, more akin to an opinion, could be a plausible explanation, but isn't required to be one. So A, B, or C, think about it for a moment and then show your answer. What do you think? Again, cup it so that no one can see next to you. Only we can see. And hold it up high because people in the back are short because you're behind everybody. Good, thank you. So from my scan of the room, I see maybe half or B. And then there's a few C's, a few A's. But most are B, it looks like. What do you think, John? Yeah. OK. Yeah, there's more B's than anything else. OK, so more B's than anything else. All right, so I'd say the majority of people, at least half, selected B, more akin to a law, a well-tested explanation. But there was some A's and C's. More akin to a hypothesis. So maybe just a synonym for hypothesis. More akin to an opinion, even weaker than a hypothesis. All right, so here's where theory fits in the scientific pantheon. Hypothesis is the lowest thing you can have. It is a plausible, testable explanation for a phenomenon that can be disproven. But it doesn't mean it necessarily has been yet. OK? Doesn't even mean it's right. Doesn't even mean it's right. A model results from a hypothesis that has withstood many tests. So it's held up. But that doesn't mean it's the best and most complete explanation. If a model continues to withstand tests, and from a hypothesis to a model is typically decades, from model to theory is decades to a century. And from theory, theory is very powerful. Theories are more powerful than both hypotheses and models in science, because they not only explain, they include facts and other hypotheses and models, but they have powerful explanatory abilities. So a theory is an extremely well-tested, tested for at least decades, if not at least a century, explanation of a phenomenon or many phenomena. OK, so the theory of gravity, the theory of quantum mechanics. The theory of relativity. The theory of natural selection. The theory of germs. The theory of plate tectonics. These are all things that explain aspects of the natural world and they've withstood at least decades, if not at least a century of testing. It's a little hairy as to when you go from theory to law. It's not like we vote on these things in any scientific discipline. So it just kind of happens at some point. People stop using theory and start using law. Same with model. People stop saying model and start using theory. That's very subjective and human. OK? But theories are extremely powerful. They're just below laws and somewhere below facts. All right? So let's do a clarifying concept here. A scientific theory is a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses. It's very powerful. It's actually in a way more powerful than facts because it explains them. All right? Just like a hypothesis that has been tested explains observations, facts. OK? You'll see these phrases, though, used a lot. You have your theory and I have mine, including talking about scientific issues. Or that's just a theory. Or this is my political theory. OK? In popular discourse, even when people in the media, science writers, science talking heads on TV, even scientists sometimes make this mistake, they're using a popular use of the definition of theory, which is very vague. It's a weasel word in popular discourse. A weasel word is a word that when you put it next to other words, it sucks the life out of them. In the metaphorically to the way a weasel sucks eggs. By the way, claim check, weasels don't actually suck eggs. So this is just an old thing that somebody decided was a true fact about weasels and it's not. Weasels don't suck eggs. But it's a good image, right? So in the same way that a weasel sucks the life out of an egg, weasel words suck the life out of the meaning of the words next to them. And so you'll see lots of weasel words. These will keep coming up. Theory in popular and political discourse is a weasel word because it's left up to you to decide what the person means by theory. And that's called equivocation and that's a bad logical fallacy. You should clearly define the words you're using if you're going to have a sensible discussion. Equivocation is bad. So leaving your audience to define what this means for them personally is a cheap way of getting people to agree with you, but not about the thing you're talking about. So it actually usually means I have a hypothesis, an untested plausible explanation, but actually even worse, it tends to mean I have an opinion. Not only is it not untested, it may be untestable and it may not even be based on observations. You may have just made it up five seconds ago, okay? Just wild speculation or a wag, a wild ass guess as Professor Cotton likes to say, all right? Without any effort or creativity. It takes no creativity to have an opinion. That's cheap and easy. That's the lowest amount of energy you can pour into any conversation is to have an opinion. A scientific theory, on the other hand, is a tested explanation for a phenomenon, okay? So that is a really powerful word when scientists say it in context and don't let the weasel word theory in popular discourse suck the life out of science, okay? All right, so I have some equipment here for a simple example of the scientific method and we'll close on this today. We got 10 minutes left, so I think that's perfect, plenty of time for an experiment. Perfect. So, let me just get, I'm gonna try to, so that people can see this. I've set up a camera on this little apparatus here and it only makes sense to turn some lights on here. We can wake everybody up. There we go, yeah, I get the retinas fried. What does an archer says on the series archer? Right, no, series like tuna steaks, something like that, okay? So there we go. We're in good shape now. You're in the danger zone? Danger zone, is that what you really wanted me to say? Okay, we'll do that. We're going into the danger zone, folks. A zone of danger, if you will. Because this is actually not safe. All right, I've used this in my E&M class, this is not safe. You may get to see me electrocuted today. So I have a bulb, all right? And it's not lighting. That's a problem, cause I need this for the rest of the demonstration. You need to light incense to appease the woe goblins. You're gonna be a problem for me, aren't you? You're gonna be that guy, you're gonna be that guy. All right, yeah, so we got wood goblins. There's a possible explanation of this. All right, that's called the construct, by the way. Thanks for demonstrating this, both of you, the peanut gallery down here. The peanut gallery would like you to know that a construct is an untestable hypothesis, okay? So it's something that really can't be tested at all. And there are many people that think they're doing science, but they're just throwing out constructs that can't actually be assessed, okay? That's bad, all right, that's not science. They think it's a strong point of the idea that you can't disprove it. That makes it strong because you can't disprove it. And that means it's not science and it's garbage. Exactly, if you can't disprove something, it's not in the purview of science, and it's therefore not science, and it's a separate conversation to be had, okay? So we're talking about science. All right, so we have a problem. I have this light bulb that won't light. I need some testable, peanut gallery, plausible explanations of why this might be. Anyone? Anyone? Is it plugged in? Is it plugged in? Now what did, what's your name? Austin. Peanut. So Peanut here wants you to know that it may not be plugged in. I'm seeing some skepticism in the middle here. Daniel, is that your name? Yeah. Yeah, okay, hi Daniel. Say, I know people. I know folks who know folks. What, yeah, thank you. What's your name? Zach. Yeah, Zach, yeah. The middle peanut gallery would also like you to know. All right, so, okay, what was that? What principle was just applied here? Does anybody know the principle that was just applied? What would you call that explanation? Complex, simple? It's not plugged in. Simple, okay. Choosing the simplest, plausible, testable explanation is a principle known as Occam's razor, okay. It's, I have this in the slides. You can look at them offline. They're also in the lecture notes. You can look at it offline. But Occam's razor is a principle that scientists often apply. You pick the simplest explanation for why something's not happening. So what else, not so simple, because I'd have to not invent these tiny little invisible things that are in the bulb, they're burning it from lighting, okay. Unplugged, ah, that's nice and simple, okay. That's Occam's razor. And in fact, it's a little hard to see here, okay. So, let there be light. Sam. Let there also be polarization in the plug. There we go. Ah, what just happened? What else? What did he just do? You. What else? That's it, no more freaking Silmarillion for you. All right, so what just happened? It failed. It failed the test. Is the hypothesis proven or disproven? Disproven. Disproven. So that's a good hypothesis. Thank you. Let's have a round of applause for the disprovable hypothesis. For the what else? Ah, what is that, a golf club? Come on, people, put it together. Are we flackin' for the what else? No, no, for the plug thing. All right, so that's great. All right, so that hypothesis was disprovable and in fact disproven. The light bulb still doesn't light. So, we need some more hypotheses. What could be wrong? Light bulb is out. Light bulb is out, meaning it doesn't work, right? So, the light bulb could be the problem. Okay, great. So, I have a pack of fresh light bulbs that I stole from our department. Careful, you can thank Fred Olnes, the chair of the physics department for this. So, there's my maybe non-working bulb. Let's find out. Okay, so what we're also doing here is we're basically also testing the hypothesis that there's a problem somewhere in this wooden board, crappy wires, whatever this thing is, and that really frayed cord that's sitting right there, right, but just inches from my hands. Interesting. So, there's a problem in the circuit maybe. So, let's take a look. Or it could be that this bulb is also fried. Or it could be that this plug doesn't work. Cause this was supposed to light. This is awesome. This is science. It's not working. Should I lift the cable? Would anyone like to see me touch that? No, we're not gonna do that. Another outlet, what they can hit trouble with that one. Let me hear that. It could be, you know what? I'm gonna test the hypothesis that it's the extension cord. It could be too. Fascinating. Okay, this is great. Because this worked before class, and now it doesn't work at all. Let me try another bulb. I'm gonna tell you something. The secret to science is that you learn a lot when you fail. There you go. Got a boom bulb. So, what did we just learn? Your fret oldness is a cheap, cheap chip. Puttin' these crappy bulbs in with the good ones, okay? So that works. Yeah, good, I have two demonstration bulbs now. This is great. All right, so we know that there's a problem not with the circuit, but with the bulb. So how can we test that hypothesis? We gotta figure out what's the problem? What's the problem? Any ideas? What could be wrong with the bulb? Any ideas, any testable explanations? Nah, you already did one. Come on, somebody else. Someone else participate. What was the constructive property? Okay, what was the constructive property? But okay, drill down into that. That's a really vague statement. We gotta have something we can test. What are we gonna test? What's the most obvious thing that can fail in an incandescent light bulb? Anyone, anyone? Does anyone know how an incandescent light bulb works? It's what else, folks? No, it was beating on the... No, it was beating on the other one. It was hitting on the hammers and like sickles and stuff. No? Maybe they ran out of hammers. Maybe they ran out of hammers. Maybe they ran out of there you are. All right, I'm gonna hint you now. All right, I'm gonna hint, hint, hint, hint. A supplement. Thanks, John. All right, so who wants to be my observer? You wanna be my observer. So what I'm gonna do is I'm gonna shine a light through the bulb and I want you to look at the shadow that's cast. And tell me if that filament, let me see if I can get it to... Does that look continuous to you? I'm shaking because I'm anxious and I don't know you, I'm nervous. It looks pretty continuous. It looks pretty continuous, yeah? Okay, so the filament seems to be okay. That's a test, that's another experiment. Got this free from the Deadman research people. Very good, doing research. Okay, so the reality is that we can keep going and going, all right, this can go on forever. But won't. But won't. And the answer is that I'm a bad mean professor, okay? And what I did was I actually monkeyed with this base. I unsoddered it and I pulled the ground wire out, okay? And so simple explanations can fail, okay? And sometimes you have to do a ridiculous amount of research on something to, like this is like at your PhD in light bulbs right here. Okay, these are all parts. You didn't even know this, it has all these parts and any one of them could fail, right? So I messed with the number eight, the electrical contact of the ground, okay? So that's, sometimes it's hard, all right? Science can be hard. Finding the right answer means you have to keep trying. Now at no point in any serious capacity that I think it was what else, all right? That would be a kind of giving up. In science, that's an, you've proposed a construct, you've left the realm of science, you quit, okay? You're no longer a scientist at that point, so long. The hard part about science is tenacity. You have to sometimes dig a lot deeper. And this is why people will spend a decade getting their PhD and then doing postdoctoral research to train to become a specialist in something they truly love because they want answers. I wanna know what the basic laws of the natural world are at their most fundamental level at the moment the universe came into being at the Big Bang. I will probably, probably die without knowing the answer to that question. But I don't care because trying to figure it out using the scientific method for me is a love and a passion. It drives me. It's not all I do with my life, but I love it deeply. And every scientist will tell you, I love this deeply and I don't sleep much, I don't sleep much. I don't, sometimes I don't see my family but they're understanding and you just keep digging, okay? So don't quit in the scientific method. Just because you haven't gotten an answer that works doesn't mean there isn't an answer. You keep going, all right? And we'll pick up on hypotheses next time. Thanks very much, folks.