Rationally speaking, is a presentation of New York City skeptics dedicated to promoting critical thinking, skeptical inquiry and science education. For more information, please visit us at NYC Skeptic's Doug. Welcome to, rationally speaking, the podcast, where we explore the borderlands between reason and nonsense. I am your host, Massimo Luchi, and with me, as always, is my co-host, Julia Gillard. Julia, what are we going to talk about today?

And that's why we have a very special guest with us today in the studio, Rebecca Newberger. Goldstein is a philosopher, a novelist. She did her Ph.D. in philosophy at Princeton, and she's the author of several intellectual histories, including Betraying Spinoza, the renegade Jew Who Gave US Modernity and Incompleteness, the proof and Paradox of Kurt Goodall, as well as several novels, including most recently 36 Arguments for the Existence of God, a work of fiction. She's also won an impressive slew of awards, including the MacArthur Genius Grant in 1996 and the genius, our first genius, aside from us, of course, our first accredited genius.

And this year she has won the American Humanist Association's Humanist of the Year award. And we also just found out she's about to be crowned this year's Freethought heroine by the Freedom from Religion Foundation.

Who did you rescue? Wow. Rebecca, welcome. I can only imagine how crowded your trophy shelf must be by now. Oh, thank you. It's a pleasure to be here. If you want to if you want to unload any of those extra trophies on any one I've got from space.

I'm really waiting to see what that Freethought Heroine Award looks like or the Freethought heroine, Cape York, but hopefully special powers.

So the initial impetus actually for having you on the show was that our producer, Beny, had read your book Betraying Spinoza and just raved about it. I actually I haven't heard him this enthusiastic about a book in a while. And so maybe as a favorite of many, we can launch right in by talking about betraying Spinoza.

So it's a really interesting title. Do you want to explain what in what way Spinoza is being betrayed and by whom?

Well, so many ways. Let me count the ways they betrayed him.

The first thing was I was approached to write a book for a series called Jewish Encounters, and it's about it's contemporary Jewish thinkers encountering past thinkers.

And the editor was very keen to have me write something, took me out to lunch. And I said, you know, I turned to a man called and I said, listen, the only philosopher from a Jewish background that I would be interested in writing about would be Spinoza. But to write about Spinoza from a parochial point of view would be a betrayal of Spinoza, the great apostle of universalism. And and, you know, somebody who was excommunicated from his own community, community and whatever parochial point of view.

Well, just looking in from a sort of Jewish point of view, what is me what is Spinoza mean to the Jews trying to turn him into a Jewish thinker? He would not have appreciated something.

So I thought that that would be, you know, a betrayal of Spinoza. Also, there are other ways that I felt that I betrayed him because I write somewhat about his personal life or even worse, as a novelist. Try to imagine my way into his inner life. And this is, you know, I think a double a double betrayal of of Spinoza.

He was a very quiet person and didn't shy quite a bit, sort of the limelight. Right.

He had friends, but. Oh, he did. He had friends. But he really was often trying to escape them. You know, he kept moving to, quite frankly, places to to escape.

And he didn't I don't think he thought the personal life was all that interesting or important, that to the extent that we're rational, we almost all share the personal identity.

That's what we should be aspiring towards. And so the the contingencies of one's biography are, if anything, hindrances. One wants to get past that sort of thing to a universal outlook. And to the extent that we all view things of speculator and a tortoise, his his his phrase, we are being rational and and that's the way we ought to be. So I just felt it was a betrayal. But, you know, for me, it was I mean, all books are was a real voyage of of of discovery.

Discovery.

I felt like I did understand Spinoza better, even his philosophy better at the end of it, seen him in the context of Jewish history and talking about his philosophy that apparently often gets misconstrued or misunderstood.

And you can comment on this is is this idea that he didn't believe in God. But I had a different concept of God, certainly from his contemporaries. Yeah. Which is part of the reason why he got into trouble. Yeah.

But the very often people think of Spinoza as equating God with nature, but in fact it was a little more complicated than that.

Right. I am so very glad to say. Yes, I mean, this is when I speak, you know, non philosophical audiences, I'm one of the first things I always point out, you know, when he says, you know, do you see Inotera that thing which can be conceived either as God or as nature? It's not the nature of babbling, Brooks or even, you know, the Big Bang. I mean, it is. It is.

It's nature as a string theorists.

It's the final theory of everything is what it is, is really the final theory. That's impression I got.

That's so far ahead, obviously. Wait, wait. Before anybody could talk about five years of everything.

Interesting to me, because actually some of my best.

I don't know, readers turn out to be physicists and and string theorists in particular, the idea that the math can explain everything, that everything falls out of the bath, out of the abstract, very, very attractive to them.

And also the idea that, you know, that there's a theory that explains everything, even why it must be the unique theory that this is truly the final theory of everything is a very it's a very appealing idea. And I you know, I do believe that Spinoza had that idea. He he has such an outmoded terminology, a vocabulary, a medieval, you know, substance and attributes and essences and all that money.

Was it the threshold? They're basically medieval. And what what year did he. Well, he said those things, right. He was born, you know, 16, 30. Thank you. He died when he was, I guess, 42 years old.

So, you know, he's right there. You know, he's overlaps a little bit with Descartes. He is an older contemporary of Leibnitz. They do need Leibnitz ripped him off terribly.

They shouldn't read. I read those.

But before we got to Latin means I can't say for just one more second because so Einstein famously said that he believed in Spinoza's God. Now, in your opinion, did actually Einstein know what Spinoza's God was, was or was he did he come up with his own interpretation?

Which did the Einstein actually equate? In fact, like most people do, Spinoza's God with nature, or was he actually more nuanced about?

Oh, I think he was very nuanced about it. I think he knew exactly. I mean, that this was his notion of sort of the unified field theory, this this theory that was so complete. It explains why it has to be the theory and that somehow, you know, the the world itself falls out of this theory, you know, that that it determines everything that that that's an idea that's very dear to Einstein's heart. And I think it was just so very clever of him.

There was there's actually to say, well, you know, I believe in Spinoza's God because that sounds good. I mean, that's what I say to my family to, you know, get off my back. I believe in God.

Of course, for the time being, Spinoza was actually essentially being an atheist and that's why people got in trouble.

But they, you know, well into the age of enlightenment can't get into how to defend himself against the charge of being a closet atheist, which meant, you know, a determinists, a fatalis and immorality, immoral, imperialist and immoral for somebody like cunt.

It's just really bizarre. Yeah. Yes.

But there was this whole pantheism straight in the bin in Can't Stay where this fellow his name is Giacobbe, and he was an anti enlightenment figure and wanted to argue that the Enlightenment led to Spinoza ism, that that was the logical conclusion and that is atheism. And so he was going to use this as an attack on the Enlightenment.

So we attacked Moses Mendelssohn and Uncombed and then all of these romantic figures like Git and Hyaena came out of the woodwork and declared themselves Spinoza's that they were Spinoza's and they kind of transformed Spinoza.

And I think part of the misunderstanding of Spinoza that, you know, nature and worshiping nature and, you know, came out of the romantics, romantics, that's the German romantics kind of twisted twist.

That's one more thing that I have to check again against the romantics, I suppose. Yeah, yeah, yeah.

One of the interesting and particularly original parts of your book is the way you show how Spinoza's personal life can actually be detected in his philosophy. Could you talk a little about that? Hmm.

You know, there's lots of imaginative reconstruction going there.

Now, for example, I didn't get into this, but my students love to or theorize that Spinoza must have had a very sad sexual history because he has just the saddest things, you know, the most depressing things to say about romantic love. It will always end in hatred. It will end in jealousy.

And so many students, you know, are always thinking, yeah, I mean, some woman did him wrong. Yeah, right.

But I don't think that that was really the great tragedy in his life. I, I actually think that he was raised in a very unique community. They were all refugees from the Portuguese, the Spanish Portuguese Inquisition. They had all been forced to convert to Catholicism. Judaism was outlawed on the Iberian Peninsula in the fifteenth and. And there were people who practiced Judaism in secret, especially in Portugal, and that's where his community that's where his family came from, and then they went to Amsterdam and they embraced Judaism.

Many of them were very disappointed in what Judaism really was because there was this all this rabbinical accretion. They thought it was just the Old Testament.

And and it was a very fraught community in which sort of the question of what is it you want? Counts as a Jew and was with constantly erupting into controversies. And Spinoza grew up with this in the midst of this fraught question about, you know, what is it to be Jewish? And I think he used a kind of Cartesian rationalism to argue that this question doesn't really matter. He it's Suchi. It's a G in the 17th century, really, the first person who doesn't identify himself religiously according to any religious wonder why he was kicked out from his community.

Exactly. Exactly. And I think, you know, that that issue was so fraught in his community and he was thinking this way, past it in such a radical way that, you know, I still think he's a very radical figure today.

But that wasn't the only by far not the only controversial position that Spinoza took. Right. For instance. He did not believe in free will and his positions on ethic also was very unorthodox. I mean, he really thought basically that ethics is a human thing and it's it's a matter of relative good and evil as is as universal concepts don't exist. It's all about human human experience, right? Yeah. Yeah, right.

There must have been a very unpopular and unusual position because he I don't know how much of that got out. He was excommunicated at the age of 24. We're not even exactly sure why. And he didn't publish the ethics until well, it wasn't published until after his death, his friends. That's because of these violent reactions to his first.

Exactly. He was trying to make, you know, I think one of the one of his aims in writing the theological political treatise was to try to make it safe to publish the ethics. And the reaction was, yeah, exactly. You know, he saw that it wasn't possible. So I don't know how much was actually known about, for example, the view that he his views, views about ethics and that he really tries to lay down on an empirical basis, that he really does think, you know, that we can discover what it is that makes human life flourish.

And that's what we all want. I mean, that constitutes a person's identity to try to persist in their being and to flourish. That's, you know, conatus as the concept of Conatus and that and whatever helps us to to to flourish is is good. It turns out that the same sort of things help us to flourish. The reason foremost reason would help us to flourish.

That reminds me quite a bit of the thinking about ethics of another philosopher we talked about recently on the podcast, which is David Hume. Yeah, of course. Came after, but it seems like is there a direct influence there or is it human? Arrived at his positions in a sort of a by another way, by some.

I think certainly I think by by another way. And it's and I think, in fact, that Spinoza and Hume are the most perfect philosophers of their extremely different types that, you know, Spinoza there has to be a deep necessity underlying everything. And and, um, of course, rejects that. You know, it's and they both follow their their intuitions about this, about necessity and contingency to the extreme conclusions, you know, that there and that they need about ethics.

It's just beautiful, isn't it?

And interestingly, of course, the canonically Hume is part of as an empiricist. And on the other hand, there's rationalist. So they are from a philosophical perspective, they are, as far as you can see. Right.

So far and metaphysically, you know, the sense of, you know, is this the only possible world? Spinoza says yes. And you certainly says no. And yet when it comes to ethics, there's there's there's such agreement which proves that therefore you must be true.

That argument, I'm still a little bit confused about his beliefs about God.

So I've heard people say similar kinds of things about God before that.

Well, I. I believe in God. But to me, God is the.

Priority of everything are to me, God is the unknown or to me God is, you know, the world nature. And it always seemed to me like they weren't actually making a claim. They were just deciding to apply the word God to something that we already know exists. And so is that is that what is doing? Is it is he just sort of redefining the word God or is he actually making an empirical claim or what?

Yeah, I mean, you know, there is the claim that God, he says, is not transcendent. God is imminent within the world.

So he's there is some rationale for using his view of what the world is, which is very different from our usual view of what the world is to to think of that as God is God like it is the thing that provides its own explanation that to us to understand it is to know why it must exist.

So it is the the of the thing that explains itself, that causes itself.

It is something that can lift the contemplation of it. We we can't understand it entirely because we're finite and it's infinite.

The explanation is infinite, but the contemplation of it lifts us out of our puny, petty point of view and puts us in a state of worship, a kind of transcendent state. And so it's a it's an object of awe and and it transforms one to contemplate. It's being transformed your life. It pulls you out of your own life in a you know, in a went in and enlarging way.

And so there is this kind of set. There is something divine and transcendent about this contemplation. So it's not a complete misnomer. I think.

So when when I was reading my notes about Spinoza, I had the same thought that that you mentioned earlier about, oh, this sounds a lot like sort of metaphorically speaking, certainly sounds a lot like string theory or even multiverse theory. And then I found these this thing in my mind of saying something about the world, our universe, our world has certain attributes, according to Spinoza, in particularly thought an extension and his idea was the God. Those are two of God's attributes.

Yes.

But that God has infinitely many other attributes that are not that do not belong to this world. That idea brought to mind.

OK, well, so I can think of that as this universe has a particular set of laws, for instance, and things work in a certain particular way. But in other universes, part of the multiverse, things work in a completely different way. There are different attributes, the different laws now.

And, you know, one cannot say that that is what Spinoza meant. But that does that is a coherent interpretation, I think.

I think so, too. I think so, too. I think actually the multiverse would go down. Well, you like the multiverse would be on board with it.

I mean, another way another thing that he might have had in mind is that these two attributes are it's a kind of it's the one contingent aspect of this system that there are two I mean, just this brute number two, and that that might be a measure more of our own finitude that we can only conceive of of these two, and that both of these attributes extension and and thinking carve up the world in different ways.

It's exactly the same world. But the laws we get out of extension, which is physics and the laws we get out of thought, which is psychology, carve up exactly the same world, but in in two different ways. And we'll never be able to get. He's kind of a dual aspect here. Yes.

Yes, exactly. It's it's it's monism. But without reductionism, because we'll never be able to have one system absorb the other system. These are completely, you know, complementary systems describing exactly the same thing, but carving it up in different ways. And when he says that God has infinite attributes, he may be saying, you know, and there are infinite not a number of other ways we could carve up this universe different, you know, different sciences that we we have no conception of.

So that the two is simply a measure of our own finitude, which is a mind boggling idea.

I wanted to ask you something about your sort of dual approach, I guess, to these topics as both a philosopher and a novelist. One of the things about Spinoza, you mentioned earlier that he had an influence on, say, goat, some of the romantics. He also had an influence on George Eliot, who apparently translated that.

Yes. And and one of my favorite writers, Yogi Luis Borges. Yes.

So that brings up the whole relationship between philosophy, I guess, in fiction. Yes. And literature.

You are way into that. So but it needs to the first time, I think that I meet somebody who was actually that much into, you know, started that much the to the two world.

So to mine, the comment about that kind of experience, I just I, I actually just finished writing a chapter for The Oxford Handbook on Spinoza, edited by Michael de la Rocha on literary Spinoza, on all of the uses of Spinoza. And, you know, and that's how I found out about the romantic usurpation of Spinoza.

But oh, yes. So this this thing. Look, I set out to be a philosopher, and my first love was philosophy of math and philosophy of physics. And I loved novels. I loved.

But I it was a kind of a shameful love. You know, I was not I didn't think it was important novels, and I just loved them. I mean, it was it was almost a physical need to read them, especially, you know, novels of ideas. But I I didn't know what to do about it until I wrote. I just happened to read a novel.

I mean, it was it just it just kind of look what I could say. And it was the summer I was I was just a professor of philosophy. And I finished my little journal article, which I was so bored with. I didn't even proofread it.

And then I had simply been handed this novel. I been handed a first line and I knew it was it my voice.

I knew it was actually going right or it was a novel and that and I wrote it.

You know, I you are sending a whole bunch of people with writer's block in the audience right now into conniptions. So this is how work, you know, and I wait and wait for a voice to hand it to you. Well, it never happened again.

I tell you that I've written, you know, quite a few novels since and a lot of short stories and that it never happened again. The first one was at the mind body problem.

And, you know, it didn't work on the mind body problem my dissertation was on. Well, I guess what we would now call the hard problem of consciousness, only it was pre Chalmers, why do you call it that?

And I had work with Thomas Nagel at Princeton. And, um, you know, it was it was kind and it was sort of funny to say to call a novel the mind body problem. Everything about it struck me as funny, but also serious. And I struggle with it still.

This this thing of being a novelist and putting a lot of philosophy into my novels.

And I think I don't know, I I somehow learned something about philosophy by doing that.

I hope the nasty itself was funny and serious at the same time. I mean, some of the things that were happening to the main characters were. Yeah.

I mean, and then, you know, there is this thing I didn't even know that had happened. But she has a mattering map. She, the protagonist, Renee FOIR, is a woman who, you know, in some sense has every gift. She's very pretty and she's very smart. And, you know, she's so miserable, you know, and I was trying to figure and my editor said, why are you so miserable? And I thought, well, she just she feels like she doesn't matter that I was trying to sort of conceptualize this.

Why does she feel that she doesn't matter. And I came up with this idea of the mattering map. Well, then I was talking at Berkeley and somebody who was in psychology said, do you know that this notion of the memory map is now a theoretical construct? Psychology, sometimes you get credit for it, but you usually don't know it within the context of a novel trying to understand this character that I came up with, something that maybe is useful and that happens.

It happens in the novel. You touch on all of the major aspects of the debate about mind body. Right. That the different theories, as you were you were saying you were mentioning Nicole earlier.

Yeah, yeah, yeah. And my protagonist is pretty is pretty obsessed with that problem. And then she's she's married to this mathematical geniuses, this mathematical genius. I made it plural because I have so many mathematical geniuses in my life. I don't know why they they keep popping up the last one. That is a mathematical genius, too. But she's married to a dualist. That's why you made it plural.

That's right, there's two of them. It's a refreshing integration of ideas with fiction because I've in the past been quite drawn to things that were built as novels about ideas or novels about philosophy. And they often tend to be this other they're sort of very vague and fuzzy or they tend to be this sort of like philosophy textbook then into stories like was a very popular book called Sophie's World. Yes. He's going to write. And it basically just you know, there's this story in every chapter.

They take a break to talk about the history of philosophy. And it's really barely, barely an integration. So I think it's very hard to do.

And I finally I'm am one of my great loves is is Plato.

I mean it Spinoza, Plato and Hume. You know, these are my great and.

Yeah, but you on Plato, he banish the art of the poets from his utopia and this bugs me and it's always bugged me. And I have constantly I constantly hear Plato in my head. I am constantly trying to come up with a defense for what I do.

And I've come up with my latest theory is that and I don't you know, it's something that gives me a little bit of trouble.

But I actually think it's true.

I think that these philosophical questions are outlining the limits of our understanding. These are questions that we are just smart enough to ask and not not answer and that our our our character, our personality, our orientation, our emotional self comes into play in our intuitions about these things. And, you know, so do we believe that the world is it is necessary or is this is the only possible universe or do we think it's all contingent? And do we think that, you know, everything is what's our basic gut intuition about free will?

Are we willing to work all our ideas just so that we can? Proclaimers Salisbury? I often think that's the case with with Conte that he just had to have passed to have to have it, even if it leads to inconsistency or are we, you know, willing to go with Spinoza and say, no, we're not for it?

You know, this is an illusion that these got intuitions help, help to shape our our worldview and our philosophical opinions because we're floating out there. We can't really answer these things.

And so and that's why I think I'm really trying to do in my novels is show how character plays into our philosophical opinions and intuitions.

Interesting, because I'm sorry, I say, you know, Plato and of course, you know, he's one to talk. I mean, his entire canon, essentially these fictional dialogues.

Exactly. Exactly. I mean, the liberties that man takes. But he's a real character, right?

Yeah. And he writes so beautifully. Absolutely. And uses every trick of the trade.

I still think that the Euthyphro is one of the best things ever written in the Western canon.

Frankly, Euthyphro is superb for the Euthyphro. And that argument.

I mean, that is the argument, the argument for those who try to say that we need theology to ground religion, that is to give them the Euthyphro.

So I had wanted to ask about your discussion of how our intuitions, our emotions shape our philosophical views, because this is something I've talked to a lot of philosophers about. And I've I've generally been surprised at how much explicit weight philosophers are willing to give to intuitions and making their arguments.

And so I wanted to find out whether you thought that these very personal intuitions and emotions actually should carry as much weight as they do in philosophy or whether they're things to struggle against and try to try to overcome.

Well, I think that that's why it's so wonderful that philosophy is such a precarious profession that we get together and we talk and we can argue and argue.

I mean, it it it is I think that that's very important because it's good to see that the intuitions that are fundamental to yourself need not be fundamental, you know, to other philosophers who you you you respect.

I mean, the notion of objectivity. I mean, one of the just the most basic intuition. Do you think there's objective truth out there or don't you you know, do you think that we shape everything?

It's all has to be contextualized or do you think there you know, the truth is always out there, whether it's moral or mathematical or aesthetic or physics, such different intuitions of good thinkers, good philosophers that that are.

In opposition over something as fundamental as the notion of of of as is objectivity, I mean, the hope was I mean, Plato, for example, thought, look, if you subject yourself to reason, we're all and Spinoza believes this to right there, we're all going to end up with the same point of view because reason will determine the answer.

But it doesn't.

We're not uniquely that's unique. I think what reason with a more sort of sort of put a reasonable way to understand it is that reason may agree, may lead people to agree to eliminate certain certain answers because they definitely don't work. Exactly. But it doesn't determine, you know, John and I have often these discussions about philosophy and science. I have a mixed background because I used to be a scientist until literally two or three years ago. Yes. And in physics right now, biology, biology and and so we have these decision.

One of the things that I think it's interesting is, first of all, I think of philosophers using intuition, intuitions as a starting point. And then you have to subject it to that kind of, you know, rigorous crosstalk and sort of argumentation you're talking about.

But in fact, there is also a dramatic under appreciation of the role of intuition in science. Just today, I was teaching a class at at CUNY on, you know, honors class and on philosophy of science, basically. And we were talking about the fact that the word scientist itself was actually introduced by William Wirral in the 19th century in analogy with artist. And the reason for that was because there is part of what scientists do, what philosophers of science called the context of justification that does deal with very specific matter.

It's very specific, logical, empirically based approach to things. But then there is the context of discovery. All right. How do you come up with ideas? Exactly. Well, that's all intuitions. Yeah. And we don't really have a general theory of intuitions. We don't have a general theory of how people come up with ideas. They just do like your voice. That was yes.

That was Hans Reichenbach terminology. That was his decision made with context of discovery in context of justification.

But the thing is, with in science, you know, if you have this intuition, you have to somehow tie it down to something impure or something.

You know, even the string theorists, they will eventually tie it down, you know, to something empirical.

And then you see how it pans out, whether the intuition is is is is it good or, you know, it's good or not. And we've done away with a lot of intuitions, vitalism, all these things, you know, that that were fundamental in in science, but in philosophy is this peculiar set of questions that we can tie down to to anything empirical.

I mean, we have, but then it becomes science.

And no one in science says X is true because they have an intuition that it's true. But they say that in philosophy. Yeah, exactly. But, you know, where do you start?

And I know I understand. It's really hard to work it out. You tweak out the implications. I mean, and the other wonderful thing that you can do and your fellow philosophers will do for you will show inconsistencies.

Right. And that's that's what I meant when I referred to logic, cleans up stuff, doesn't hold up to scrutiny. And it's speaking and logic. You've written about Godo. Yeah.

As well, which is lovely. And you said you had an interest originally in philosophy, in mathematics. So I guess that's that's part of it. So.

All right, tell us the basics about gold, because this gold is in completeness. Theorem is another one of those things are because there are two of them, but especially the first one, which is the one that most people often refer to. That's also something that a lot of people misunderstand. And and then, on the other hand, is very interesting for for our readers, because, as you know, it's been misused in all sorts of ways, including, ironically, by postmodernists to argue that there is no such thing as objective knowledge, which would have horrified gold, from what I know.

Absolutely. Yes, exactly. So and I think that is probably what got me to write about it, because when you hang out with you know, because I'm hanging out with scientists, but I'm also I hanging out with writers and humanists and oh, my Lord, the misuse of it.

And I am you know, when it comes to intuitions, one of my deep core intuitions is an objective truth and especially in mathematics. And so and the girls feel the same way.

Oh yes.

So and this but I mean, talk about intuitions. He he was such a committed Platonist. I think that this was right the most. This was the romance of his life. He became a committed Platonist when he was an undergraduate in in college. And and that's when he I think he first was going to major in physics. And then he took this history, a philosophy course with a Professor Gumperz, and he became a Platonist and he wanted to prove.

He wanted a mathematical proof that would prove the truth of Platonism, so he won a mathematical proof for a meta mathematical proposition. So he wanted to do I mean, so audacious. And I I believe he came up with this plan when he was an undergraduate. At first he was in number theory.

And then he somehow who knows how because he was so secretive, switch to logic, somehow saw the potential for transforming logic into a vehicle of trying to prove a mathematical point of view mathematically, you know, and he does, you know, the two languages that are there, you know, those propositions is that it's the most amazing, beautiful proof, because every proposition, every arithmetical proposition has two meanings in in the proof, the straightforward arithmetical one and something meta mathematical.

It can talk about its own provability within the system. So there is a kind of merging of mathematics and mathematics.

You know, he thought that he did proof plainness because he proves that he pulls apart the notion of provability and truth, that there are in every system of mathematics, every consistent system of mathematics, rich enough to express arithmetic. There is a proposition which is true, but unprovable.

And we can see that it's true, but it's not provable. So he's so pulling apart these two notions of truth and provability.

I'm so glad I have you here because it's always been so difficult for me to understand what true but not provable means, because I was saying that it's true if you it.

So can you. Yes.

Well, that's very amazing proposition that we call now. The good old proposition comes up.

It has this arithmetical meaning, but it's also saying about itself that it can't be proved in the system, in this complete system. And the way that we see that that is true is that if that proposition could be proved in the system, it would lead to a contradiction. So which proved by contradiction.

So we know that this proposition is true.

That is that it can't possibly be proved true, because if it could be proved true, it would lead to a contract to work like a bit of a smart ass approach to it.

Smart. Exactly. But it works because it's self-referential. Exactly. Yes, it is.

So why would we have this problem if we just sort of, I don't know, compartmentalize all the self-referential statements, put them in a box and said, let's just let's just ignore these and endure with, you know, math and logic without them?

Well, what's wonderful is that he takes this horrible affront to our intellect, paradoxes. You know, they're terrible. You know, the mind just boggles at them.

And he transforms it. He uses it. He makes use of it.

He turns it into a proof to show that there is and in every consistent system rich enough to express arithmetic, there will be a proposition which is true. And we can actually see not using the instruments of formal proof within that system, but sort of going outside the system and understanding what the proposition is saying. We can see that proposition is true, but we can't prove it within the system. The other thing, the second theorem says that one of the things we can't prove within a system is the consistency of that system itself.

So it is also upsetting.

Did this result have repercussions and philosophy?

And what basically undermined that was a big time in logic and philosophy in mathematics. Right. So you had Bertrand Russell and why did mathematics. Right. Right.

Well, he used their system because we knew that that was consistent. So that was the system that he uses for his language.

But the person he really torpedoed was David Hilbert, who was who was the preeminent mathematician of the generation before and wanted to formalize all of mathematics because of the paradoxes and said, you know, so there was this program to formalize everything and to show that all truths to be captured in formal systems.

And that's exactly what Girlschool couldn't be done.

What about outside of logic and philosophy of math? Did it have any impact on, say, epistemology, what philosophers thought could be known?

Yes, I think so. But there's here's a sad thing. That's where the problem comes in. That's where the postmodernists would say, oh, that's why I'm wondering how much influence and how much it should have influence in different things, even within philosophy itself.

There was you know, there was disagreement about the interpretation of what it really meant. And that's the sort of interesting thing to want to. To end discussion, he wanted that the precision and the rigor of mathematics to prove the mathematical position that he loved and he truly loved it and and he didn't do that.

You can't do that because there's always a way of going at these philosophical opinions that you can argue about. Vic and Stein, for example, didn't he wasn't a Platonists he knew of of girdles proof. He talks about it and foundations of mathematics a little bit.

Now, this is going to be on a lighter side, but I want to talk for a minute to talk about the story about Gödel and the U.S. Constitution, because I found I find that that is extremely amusing and probably give you some insight, actually, that the man's character. So you wouldn't want to tell the story.

Yes. So he took it very seriously. So goodo. He came here, you know, from from Austria during the Nazi period. And he was not, by the way, Jewish.

He was often he wasn't he was often mistaken for, look, Jewish when he was associated. One of the reasons he got in trouble with the Nazis, because he was of his association with the Vienna Circle.

Yes. And that was you know, they were and Hahn, who was his his dissertation advisor, was Jewish. I mean, you know, he was he hung out with a lot of Jews, but he was not Jewish. But he did he did actually get beaten up by some brownshirts. They knocked off his glasses and his wife, Fidel, fought them off with her umbrella.

Yes, adorable. And Lee came to the United.

Might be the most adorable story involving Nazis.

Yes. Adorable story. Don't go together very well at the low carb. Definitely.

So, you know, he they finally they came to Princeton, to the Institute of Study. Einstein was already there.

They became good friends with a legendary friendship. When I was writing the book, I interviewed people. I got him just in time because her art, they all died soon afterwards, who knew about their friendship? And one mathematician said to me they wouldn't they didn't want to talk to anybody else. They would only talk to each other. So Einstein was quite old and girl was young, very different personalities. But they really and they both believe very strongly in objective truth.

I think this and were upset about the misunderstandings of their own famous although open parenthesis.

I want to go back to the U.S. Constitution, OK, in parentheses, didn't go to give as a present to Einstein on his 17th birthday a paper that actually caused Einstein to have troubles about his own.

Well, yeah. I mean, he said that it it works out that one is, by the way. Yes. One of the models for general relativity is cyclical time. All right. And Einstein said he was aware of that.

He but he didn't like it, which will make it time travel possible. Exactly. You know, he didn't like it. He didn't like it exactly. And he didn't like it. He didn't like to see it worked out so rigorously. He was sort of in the back of his mind. This might be possible.

I don't think I remember. OK, back to the.

OK, so Einstein was already a citizen girl, studied for his citizenship. He took it very seriously, took everything very seriously.

And he was very upset because you seem to have discovered a problem with the Constitution. He saw a way in which democracy could collapse into into totalitarianism and the constitutional way as the constitutional way in which that could happen.

And so he you he wanted to talk to people about it and he was very obsessed about it. And then he got in. So Einstein was taking him to his meeting with the judge who was going to test him and give him citizenship. And he got into the car and he and an Einstein was the delegated distractor.

He was not supposed to let go to think about this constitution, all the talking. And then they they they arrived before the the judge who had been the judge, the same judge for Einstein. So he knew him and was very, you know, very friendly. And then the judge opened up by saying, you come from your come from Germany. No, on the contrary. I come from Austria said, well, in any case, your country is now under totalitarianism.

This could never happen in the United States is the worst thing I would say. And Colonel, on the contrary, I had a quick look between Einstein and the judge and the judge said, oh, I don't think we need to go into that right now.

So unfortunately, we don't know. So what are we don't get all of a sudden never wrote down that thing? Well, he might of you know, he used this special a shorthand that he learned as a high school student. Is this Gobbles Hober I can't remember the name of it, but it's a shorthand.

And so there's somebody who's been translating all of these notebooks from the shorthand is German. It's not bad in German, but in the short. And so they haven't gotten around to the notebooks. I mean, of course the first material that we have no interest in the first priority is the logic, you know, the math and.

Well, I don't know I don't know what I should do that I would have to go to.

However, I also had a much darker side. Right? I mean, he actually basically starved himself to death at the end because he couldn't be fed by his wife, right?

Yes. She was in the hospital. She used to she was used to feed him, taste his food.

And she was like she was probably about he was paranoid and he had been paranoid. You know, even he even had episodes of paranoia back in Austria when he was a young man.

And but interestingly enough, lightness features in this. Oh, I instantly said, you know, Einstein loved Spinoza and Goodall loved Leibnitz.

They were both rational as these two men who would walk back and forth from the institute every day.

And, uh, he he still he believes very strongly in a principle of sufficient reason, girl.

And he believed that everything that happened was necessary and that there was always an explanation and that interestingly, his somehow his paranoia and his metaphysics merged together in some degree of a combustible combination of very combustible.

And I have to when I was teaching, the rationalist attempted to rationalize. I would sometimes have students this was at Columbia who who were also verging on sort of paranoid. And the notion of like an explanation behind everything was very appealing.

But I can I can see the sort of conceptual connection between.

Yes, between those two. I'm so glad I abandoned that. The principal and a number of very fundamental we are now over time.

But I thank you so much for for all of those. Oh, fascinating discussions of both Spinoza and got all my pleasure and your own process.

And so we'll wrap up the section and move on now to the rationally speaking, PEX.

Welcome back. Every episode, we pick a suggestion for our listeners that has tickled our rational fancy. This time we ask our guest, Rebecca Newberger Goldstein, for her suggestion.

OK, I think I might be accused of nepotism here. Oh, go ahead, but go ahead.

Well, Steven Pinker. Yes, we have heard of him. Yes. He is about to publish in October a book called The Better Angels of Our Nature Why Violence Has Declined, which is really shocking.

It is. It is it is a long book and it looks at measures of violence of every sort, war's duration of wars, intensity, no matter how many big powers get involved in wars, homicide over what I what time frame is starting with the hunter gatherers.

And we have the whole shebang.

The whole shebang. Well, you know, we we have there are still hunter gatherer communities. It turns out Hobbs was right. Rousseau was wrong.

The most dangerous place to live is in a hunter gatherer society, yet a state of nature. Yes. So is romantic, you know, funny thing, we covered Rousseau in the same episode.

We covered Jum. And boy, did I have already bad reason but a bad argument with Weaver. So I only got vindicated by it.

Exactly. Exactly. But in and it's, it's, it's shot. We, we tend to think that we are living or that we've been through this in the 20th century, the most violent period in history, and that's actually completely false. Now he's a big supporter of, you know, human nature. It's not human nature that's changing.

But we we learn and it turns out one of the most important instruments for making us less violent is Reesa. The Enlightenment had a huge effect on homicide rates as you watch the Enlightenment spreading from from Amsterdam to London. And, of course, literacy rates are going up and that helps a lot, too.

But you actually can plot the you know, they had plotted the homicide rates and they drop.

But we are living actually in the least violent time in human history. It could all be reversed. We have terrible weapons. Hopefully it's not a risk before the book comes out. That would be accurate.

Oh, another thing.

Think it's interesting, the way you just put it again reminded me something that we talked about pretty recently about him. So I read I read recently a paper on Jim's conception of human nature. And it turns out that you had an interesting position, big surprise there.

You know, he often had been, but he was involved in this debate in his time when where some people were saying, no, look, human nature is horrible. We're horrible creatures, we're selfish and all that. The other side was say, no, we're very social, we're very cooperative and so on. But both sides assumed that human nature was unchangeable. Yeah, Hume's position was much more nuanced and I think much more modern, which is and he basically said, yes, there is some fundamental things about human nature.

We started in a certain way, but in fact, society, culture and therefore also reason changes things and it alters them sometimes in, you know, long lasting terms. And it sounds like that's is exactly right.

I mean, culture also, you know, can can have a terrible effect. And it turns out the most dangerous thing and this is a book with, I mean, just an incredible amount of empirical data graphs. And I called it his graphic argument.

And I think there are a hundred graphs, but the most dangerous thing for our species is ideology. You know, whether it's religious ideology or secular reality, it kills.

And and that is I don't know. That's that's a topic that's about. That's right. That's up, I think. And we'll make sure to have a link to that, I suppose, for preordering now and and soon enough for ordering underneath the building to this episode on the Russian speaking podcast website.

And we now are well out of time. I'm afraid this has been such a pleasure. Rebecca, thank you so much for joining us. Thank you for having me. Thank you.

And this concludes another episode of Rationally Speaking. Join us next time for more explorations on the borderlands between reason and nonsense. The rationally speaking podcast is presented by New York City skeptics for program notes, links, and to get involved in an online conversation about this and other episodes, please visit rationally speaking podcast Dog. This podcast is produced by Benny Pollack and recorded in the heart of Greenwich Village, New York. Our theme, Truth by Todd Rundgren, is used by permission.

Thank you for listening.