Humanities but tonight we turn attention to the sciences albeit with a heavy dose of the humanities on the time. Our guest is doctor michael strevens, born and raised in new zealand he moved to the United States in 1991 earning his phd at rutgers university. Now a professor at new york university, his book, the knowledge machine how irrationality created modern science, is i think critically important at the time when distrust of science is on the rise. The book begins with a simple question but not at all a simple answer. Why does it take 2,000 years after the invention of philosophy and mathematics for humans to start using science to learn the secrets of the universe. The answer as it turns out might also help us better understand why we should have more faith in the Scientific Community. Doctor strevens, thank you very much for joining us. It is great to be here. I will talk a little bit about this book and about what im setting out to do with it. So, i wrote this book to answer two Big Questions that i had about science. One of the questionss simply how is it that scien is so successful, it reveals to us the secrs of the universe and it tells us how strings of molecules can create life, its taken some of us to the moon [inaudible] what is the lifeline to the truth to all of this knowledge . I took a glance at this question and i think its certainly on the right track it has something to do with evidence. Theres something about looking out into the world gathering evidence that makes science very powerful. You might summarize it like this. We give a theory only if it agrees with what we see out there in the world and give credit if it agrees with what we see out there. But i think the story about evidence cant be the entire explanion. And heres why. These words were first written by aristotle greek philosopher, writing about 2,000 years ago and also thought it was very important they should agree with the fact. But he didnt invt a science. For all of those marvelous discovies and technologies we had to wait another two millennia. So, sothing is going on in modern science and certainly looking at the evidence that wasnt around in aristotles time, and that the that is what motivated me to pose these questions. One is a more specific question about the success of science. What is it modern science is doing with the evidence that makes it more successful than the ancient greek philosophy much as [inaudible] and why did it take so long to figure out how to do it that way . My inspiration for this comes as a philosopher of science from an idea which i think is beautiful and deep but also a little bit wrong. In my book i take that idea and i change it a little bit into something that i think really does answer these questions. The idea that i begin with is due to the most famous philosopher of science, who wrote in the middle ofhe las century the most famous bk called the strture of scientific revolutio published in 1962. And its in this book he laid out his view of scientific progress as a series of what he called paradigm shift. So his idea was at any particular time a Certain Branch of domain, science, astronomy or some type of physics or biology is run according to a kind of plan, a total view to which he attaches the paradigm and when there are great changes in our scientific thinking about the world one is hesitant ofhe paradigm shift so for example in the 17th century, the economical paradigm in which the planet orbited the sun is replaced by sorry, orbits the earth of course in which then the beginning of the0th century newtons paradigm in which avity is a force exerted by mass directly on others replaced einsteins paradigm, in which mass actually twists the structure of spatime. Now its very important the paradigm is not just big and exciting, but in a certain and more profound almost totalitarian sense it rules the scientists mind. As it were in some sense they were stuck in a paradigm and cant think outside of it. So how could that be that a certain kind of narrative and the refusal even inability to imagine other possibilities could be a good thing, could promote scientificrogress. So its so full of promises. What it offers the scientist is a recipe for finding the answer to any question in thearadigm scope and any question about astronomy for the astronomical paradigm and question about gravity for the right paradigm in physics. This moves us to the time when scientists are simply applying this recipe. Because they are convinced the current paradigm is correct, they think that this is the recipe, the only recipe and it is the one and only that if they follow it willive them a full and satisfying picture of the world it sounds a little more dangerous than it does promising. Why should this be a good thing. Heres what he sd. What the paradigm do, by focusing on just a few things that are terrifically important, the few problems muste vestigated very carefly. Im just going to read his word it forces scientists to investigate in a detailed way that is unimaginabl but not unattainable. What is thinking here. I will take you on a very brief tour. If you scientic experiments that will give you th a sense of the kind of detail that he thinks is essential to science and without t commitment to the paradigm would never be built and carried out. Heres one that was in the news recently and was successful just a few years ago and created the nobel prize. Its to detect gravitational waste. It consists now of several differences. The structure that you can see has to be so straight that they can detect tiny movements and it is the size of a proton. It took 50 years to build these things in a way that would finally succeed with many reversals along the way and the threat of losing experiments that produced no results. But the scientists stuck with it for those years and finally got the results. This is the kind of focus that was necessary to make enormous progress and turn out the details that matter. It is still incredibly grueling. This is the island at daphne major which is in the galapagos islands. Its about half a mile across. Two biologists, rosemary and peter, have been going to this island every summer for the last 40 years. What they have been doing there is tracking populations [inaudible] used in the thinking of evolution and theyve been following those and tracking every single growth. That requires some commitment. One of the many interesting discoveries is an entirely new species that established not too many years ago and probably about 40 years after they first got it going. Again, the focus on the detailed depth producing an exciting piece of evidence we are doing the work to carry it out. The hormone in the brain that was discovered as a result between two scientists, andrew and [inaudible] to discover the structure, the greatest obstacle wasnt some complicated theoretical question or different calculation, but simply producing enough of the substance to actually do the appropriate experiments. There he is. He says that the most important factor in this project was spending, as he said here, an entire year distilling them just to produce a few milliliters of the substance. That is the kind of focus required and the kind of detail that allows us to make progress in science. They think that it is possible and because they are, indirectly as it usually turns out, not only convinced that the paradigm is correct, and the recipe for doing science cannot fail. They push that recipe so hard they apply it to everything. They try to squeez tried to squy last drop of truth, and in doing that they discover and that is how the paradigm is destroyed, creating the need for a new paradigm and ultimately triggering a shift. The story where the real secret of science isnt something intellectual or logical. Its not some kind of a morality, but its paradigms whose most important effect is simply to provide a kind of motivation. Just as paradigms change those are theories of science, so we have to ask what is true and right. So essential to the picture that scientists are convinced the paradigm is correct or they wouldnt have the confidence in it to block out all the alternatives and just chase this one way of doing things. Many historians and sociologists that have been working since kuhn have been influenced by him and ended up skeptical that scientists really are one example, a bunch of physicists did a complicated experiment saying we want to break physics and find evidence against whats called the standard model, the current paradigm. These scientists are not convinced by the recipe but want to find a way that it goes wrong. That certainly isnt what kuhn would have predicted. Or on a much smaller scale, in a famous book on the sociology of science, in which he went into a lab, one of the discoverers of that brain hormone i was talking about a moment ago that required the extraction of so many. We dont need to look at this too closely, but he finds a place where scientists are in effect fooling around with the recipe changing the conditions for what cancels out the success in order to outfox the competitors. Instead of it being a recipe everyone accepts as some kind of holy scripture, these scientists are rather rewriting it to suit themselves, to promote their own conditions. So, here it looks like its the scientists in charge and not the paradigm. It seems that then kuhn hadnt had what he most needed, which is a kind of unthinking commitment to the paradigm. I love this story so much i want to point out some things right about it. I think what is right about it is the idea that science is a very peculiar institution for motivating scientists to perform experiments, to pick out facts, to conduct measurements that are so expensive, so timeconsuming that they simply wouldnt do these things in any other circumstances in the context of any other institution. Its a motivational technology. And its what drives scientists to uncover these facts for progress, so let me tell you a little bit about how that works. We should think of the rules of science not as something scientists believe or Something Like a religious dogma. But rather like the rules of the game. This, so they agree to abide by the rules. The most important rule is the evidence rule. I said that evidence would be critical. Only empirical evidence that that is at the absolute core. , insofar as the Scientific Method, what it does is lays down a standard for the test that tells you what empirical evidence is and says the scientific argument must be conducted in terms of the results of the empirical test. So it prohibits any kind of other argument. In particular, it prohibits for example, philosophical arguments, arguments based on the beauty of theory but i will say a little bit more about this later. Now, a rule like that is very wide open. It isnt limiting like one of kuhns arguments. It allows for disagreements. It doesnt tell scientists how to interpret the evidence they produce. In fact, they disagree a lot on how to interpret the evidence. But it does create a certain kind of consensus. Everyone agrees, all the scientists agree that first of all every argument they have is to be resolved by conducting some expiment or making some observation. And they agree which kind of experiments and observations are relent. , this means they have a kind of consensus on what counts as a move in the game and how to go on. And the reason that this rule is so important, even though it doesnt say much, is that it has the function. First of all, it simply binds the scientists together in a single argument because they agree on how to go forward. Second, it pits them against one another arguing against theory, or simply to find the truth in a way that evidence is continually generated. And because evidence is the only way to win the argument, you have to find some small fact that your theory accommodates your rivals theory. So it gives you a motivation to investigate the nature into the detail and depth. So it isnt that the scientists are addicted to one kind of recipe. The are many out there, but they are all of a certain source. They are all recipes that have that kuhn propey of pushing scientists to go deeper into the detail, than any perhaps reasonable person might care to go and the result is the progress in science, and ultimately the convergence on truth that we see. So here science is secret, a great pile of evidence, not just any evidence but a very detailed and thorough evidence. Okay while i have a few minutes left just as well because i promised to answer not just the question at the relation to the evidence is such that it should be successful but also why it was late toome along. Y was it even though aristotle clearly saw themportance of [inaudible] and forming to the observation andvaluating it and Everything Else he wrote about, why was he not a modern scientist . The answer is although he thought empirical evidence cound, he didnt think only empirical evidence counted he thought philosophy also was extremely important. Lets skip forward to 2,000 years later. We remembered the philosopher not the scientists, even though he wrote extensively about physics. Why is he not a scientist, because he also thinks that empirical evidence is not the only thing that counts to figuring out the truth. In his great philosophical system in fact he has knowledge ultimately depending on the knowledge of god. Hes a great rationalist, but he puts together his theology and philosophy and physics into one beautiful, unified package. But it is too unified that it distracts him as aristotle was distracted by his philosophy from the empirical evidence, so he doesnt go as deep. Let me look at one more. Undeniably a modern scientist, this is the Nobel Prize Winner in physics and one of the inventors. Here he is telling us that empirical evidence has been the only thing that counts. Hes saying that beauty and simplicity and elegance are also very important in deciding on the correct hypothesis. You might be thinking am i contradicting myself, that is only empirical evidence counts and yet here is a modern physicist who would like aristotle is saying other things count as well. Why wasnt he distracted from looking at the empirical evidence . The answer is that d, however much he may have personally thought that the beauty was important as many others, its nevertheless playing the science game and as brian puts it, another physicist in his book the elegant universe, and the science game to read his words aesthetic judgments do not arbitrate scientific discourse. That is they dont count. He can praise beauty and use it as an inspiration, but when he goes to argue the theories and when he publishes papers putting forth, for example, the theory, he is forbidden from invoking beauty as a reason to say his theories. All hes allowed to do is point to empirical evidence. Hes got to point to new predictions that his theories make or at least show how they can form what we already know about the particles of which the universe is made up. So, the game forces him, however he thinks in his private life, and forces every modern scientist to in the end make their case with empirical evidence. And that means they or the experimenters that are testing the theory just like those have to do what kuhn rightly thought was so essential to modern science, which is to dig out the details. And the upshot of this, and this finally will get to the explanation why science is so late, the scientific argument that only empirical evidence counts are strictly speaking irrational. It suddenly looks that way or should look that way to practicing scientists and indeed to everyone who came before. Here is a basic principle of the rational argument that every philosopher or whatever agree on. That wn you are deliberating about something important, you should take something into account. Or every relevanconsideration that is not too expensi to take into account. Someone like this thanks aesthetic reasons, the beauty of this area is highly relevant. Furthermore, it is easily available as a judgment, yet he is participating in a game of scientific argument that doesnt allow him in his argument for his theories, his public arguments, to invoke this. So in other words, the game enjoins him in the public argument to violate the principle ofationality. And in fact, ai said, the science looks so precise because of this. Scientts may not appeal to these other factors no matter how important they think they are because they must focus on the evidence. So, for the modern science to be created, for this crucial feature of science to be discovered or to b written down and acted upon, they had to somehow stumble onto the fact that this narrow rule worked very well, and that took a long time. I have much more to say about this in myook and i have many more illustrations and the thing i said about science and many moreistorical stories about the way in which the nrow rule finally hit upon. That there you can disprove any number of scientific theories but are the onethat remained its not possible to assi likelihood one of the other can you talk about where that came from . Sure. And what you just mentioned to be entirely correct but the scientists do have use that have yet to be disproven but have wildly different views. And from science and how turn on something truly objective with the possibility of the recalcitrant and cannot make that stick but the problem is with the disagreement that the tiny details and those extremely complicated way and what is involved in the case that the apparatus really isnt working. In my book i tell the story of the famous expeditions to establish einsteins theory of relativity. And those observations and then they have rather different results even i look at something went wrong. Certainly there is a tremendous disagreement and with that disagreement of what to believe but it doesnt matter. If they are producing the right kind of interact on that evidence and that relativity theory and eventually that evidence piles up and that consensus. You leading to and audience question with the early thought process, how might the application of modern science affected those discoveries . Part of the book where he talk about the idea of the essence of everything, eight modern scientific theory affected . Those are the early arguments has a great admirer of the ancient greek philosopher so another character in my book in the very early 16th century. These are genuinely scientific ideas that the world is less complicated and for all those things to see around us. Thats wonderful stuff. Back around two and half thousand years ago that was debated and thrown around. If you like the scientists that are formulating not only the connection to the evidence those who thought everything was made of water but you have certain features of the world for example. We each have their good story and looking back now two and a half thousand years later the quality of those explanations was not enough to decide between the what was needed with that small detail only by developing those interments one instruments with that particle that makes up matter. Even in newtons day we really didnt know. Over the last 200 years. Are there historical parallels in some cases rejection of science that we see today . Science is probably one of the most striking historical cases in the 19th century fo