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D
Dantzig
“'40s would be Dantzig, George Dantzig, right? Famous for the simplex method. Also famous for walking in late and seeing the two problems on the board and solving them thinking they were homework,…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 13:59 · read ↗︎
dart board
“about the situation of a dart board, okay? Suppose we're playing darts and I'm throwing darts at a dart board, and maybe I have a kind of uniform distribution of where the dart would land somewhere…” (Joel David Hamkins)
Lectures on Infinity · Lecture 2: Supertasks: Doing Infinitely Many Things▶︎ watch 25:00 · read ↗︎
Darwin
“We are the greatest living being because God gave Adam dominion over the animals, until Darwin took that away in 1859 and said, "No, we're just another animal. We're the hairless apes." And” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 7: Nietzsche's Warning to the Future▶︎ watch 10:52 · read ↗︎
David Bohm
“variable tradition or extra variable tradition. The most successful such theory we have was first formulated by David Bohm, in the 1950s. It was completely ignored at the time. Part of what…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 5: Three Ways to Save Reality▶︎ watch 1:06:08 · read ↗︎
David Hilbert
“from the 20th century. So, names like David Hilbert, Kurt Godel, John von Neumann, George Dantzig, Andrei Kolmogorov, Jack Emmons, Stephen Cook, Leonid Levin, Richard Karp, Don Knuth, all of those…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Intro: Computation and Its Limits▶︎ watch 8:04 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 1: Is There Anything Computers Can't Do?▶︎ watch 5:20 · read ↗︎
Lectures on Infinity · Lecture 5: Potential vs Actual Infinity▶︎ watch 58:06 · read ↗︎
Lectures on Infinity · Lecture 10: Set Theory's Deepest Mystery▶︎ watch 2:14 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 33:46 · read ↗︎
David Hume
“We're onto our second philosopher now, uh, David Hume. He's an 18th century Scottish philosopher, and there was a survey given a few years ago to professors of philosophy, uh, uh, asking them which,…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 3: Hume's Map of the Mind▶︎ watch 0:01 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 5: Kant Wakes from His Dogmatic Sleep▶︎ watch 3:42 · read ↗︎
David Lewis
“story in this vein, which maybe I'll take a second to tell. David Lewis, toward the end of his life, got interested in the Many Worlds Interpretation of quantum mechanics, and was interested in cases…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 5: Three Ways to Save Reality▶︎ watch 1:01:32 · read ↗︎
David Wallace
“of the many-worlds interpretation. Also, there's a book by David Wallace called The Emergent Univer- The Emergent Multiverse, excuse me. Which is what most people now would identify as reporting on…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 5: Three Ways to Save Reality▶︎ watch 52:51 · read ↗︎
Deal with the Devil
“So let me tell you about a particular supertask that I like quite a lot. It's called the Deal with the Devil, okay? Suppose you've made some really good investments, shrewd investment, and you have” (Joel David Hamkins)
Lectures on Infinity · Lecture 2: Supertasks: Doing Infinitely Many Things▶︎ watch 6:22 · read ↗︎
death of God
“And this general phenomenon is what Nietzsche calls the death of God. Have you not heard of that madman who” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 7: Nietzsche's Warning to the Future▶︎ watch 14:22 · read ↗︎
decidability
“So what we just saw, okay, this idea of easy problems, polynomial-time solvable problems, that can be viewed as a sort of refinement, a strengthening of Turing's notion of decidability. For Turing,…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 3: Easy Problems, Hard Problems▶︎ watch 25:29 · read ↗︎
decimal notation
“So, when you have a number in decimal notation, say I write a number like 8547, 8,547, what it means is, this is a positional number system, so it means that we have” (Joel David Hamkins)
Lectures on Infinity · Lecture 1: Zeno's Paradox and Infinite Sums▶︎ watch 11:39 · read ↗︎
decision problem
“problem that Turing addressed. Okay, so Gödel's result did not rule out the possibility that in the event that a statement is true, you could, in a mechanical way, generate a proof of it, and this is…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 1: Is There Anything Computers Can't Do?▶︎ watch 10:53 · read ↗︎
deconstruction
“now after his death than he was in the '60s through the '80s or '90s, but he was the creator of deconstruction. And I think Socrates' description of the Heracliteans is a bit like the behavior of the…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 3: Does Relativism Refute Itself?▶︎ watch 44:19 · read ↗︎
Dedekind
“we'll move through Galileo, and then we'll see Frege, and Dedekind, and Cantor, and the 20th century thinkers of Godel and Tarski, Russell, and so on, the contemporary ideas. To my way of thinking,…” (Joel David Hamkins)
Lectures on Infinity · Intro: Infinity Has a Story to Tell▶︎ watch 0:31 · read ↗︎
Lectures on Infinity · Lecture 5: Potential vs Actual Infinity▶︎ watch 57:27 · read ↗︎
Lectures on Infinity · Lecture 6: Galileo's Paradox of Infinity▶︎ watch 32:38 · read ↗︎
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 2:34
Lectures on Infinity · Lecture 9: Beyond Countable Infinity▶︎ watch 51:16 · read ↗︎
Dedekind arithmetic
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 21:27
Dedekind cut
“But then conversely, given any real number, given any real number, I can think about the set of rational numbers that are below it, that's called the Dedekind cut of that real number. And so if I…” (Joel David Hamkins)
Lectures on Infinity · Lecture 9: Beyond Countable Infinity▶︎ watch 1:01:52 · read ↗︎
Dedekind finite
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 3:15
Dedekind infinite
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 2:34
deep truth
“And aphorisms like, "A trivial truth is a truth whose negation is false. A deep truth is a truth whose negation is also true," okay? And you say, "Wow, I used to look up to you.” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 2: When Physics Stops Making Sense▶︎ watch 19:33 · read ↗︎
definability is not definable
“definability is not definable, and maybe it's easy to take Berry's paradox in a naive way as meaningful that he's using this word "definable," but when you drill into it and you apply the tools of…” (Joel David Hamkins)
Lectures on Infinity · Lecture 4: The Largest Tweetable Number▶︎ watch 48:51 · read ↗︎
definition by recursion
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 24:48
density
“more numbers than squares, because there's all the other numbers in between the squares, and furthermore the density of the squares gets less and less as you take higher and higher numbers. So it…” (Joel David Hamkins)
Lectures on Infinity · Lecture 6: Galileo's Paradox of Infinity▶︎ watch 18:50 · read ↗︎
dependent co-origination
“to put their view of, of reality, if you will, in a nutshell. So, nothing is independent. Nothing has this being in itself, this sort of selfhood, this, this core.... and everything is coming into…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 2: When Every Perception is True▶︎ watch 24:11 · read ↗︎
Descartes
“At this time, there was no division between philosophy and science. It was all combined. The word for science was natural philosophy. So, there were a number of figures, like Descartes, uh, Bacon,…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Intro: When the Old Map Stopped Working▶︎ watch 3:40 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 2: The Birth of Modern Science▶︎ watch 0:01 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 3: Hume's Map of the Mind▶︎ watch 0:31 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 4: Why You Can't Prove Tomorrow▶︎ watch 4:32 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 5: Kant Wakes from His Dogmatic Sleep▶︎ watch 0:01 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 6: How Your Mind Builds Reality▶︎ watch 11:00 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 7: Nietzsche's Warning to the Future▶︎ watch 3:08 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Recap: Making Your Beliefs Your Own▶︎ watch 0:22 · read ↗︎
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 2: When Every Perception is True▶︎ watch 29:54 · read ↗︎
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 5: Defeat as Philosophical Victory▶︎ watch 29:59 · read ↗︎
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 3: Two Laws That Can't Both Be True▶︎ watch 38:24 · read ↗︎
detector
“somewhere along the hard route that clicks, okay, if the electron takes the hard route, and it does nothing if the electron takes the soft route. So you insert something that's gonna tell you which…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 1: The Experiment That Broke Reality▶︎ watch 44:48 · read ↗︎
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 2: When Physics Stops Making Sense▶︎ watch 30:35 · read ↗︎
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 3: Two Laws That Can't Both Be True▶︎ watch 8:03 · read ↗︎
Determinism
“that's not the case. Suppose that you just wanna take an interest in the particles, okay? You don't care about the fields. It turns out that being given the initial positions and the velocities of…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 4: Bell's Impossible Proof▶︎ watch 46:45 · read ↗︎
diagonal argument
“And the thing that I'm gonna do when I'm defining this number Z is I'm going to make sure that the digit D1 is different from the first digit after the decimal point in the real number R1. And I'm…” (Joel David Hamkins)
Lectures on Infinity · Lecture 9: Beyond Countable Infinity▶︎ watch 4:33 · read ↗︎
diagonalization
“to diagonalization, to reductions, to show you Turing's original argument that indeed, there are problems, even natural problems you'd really like to solve, like the famous one being the halting…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Intro: Computation and Its Limits▶︎ watch 1:13 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 1: Is There Anything Computers Can't Do?▶︎ watch 36:19 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 50:59 · read ↗︎
Lectures on Infinity · Lecture 9: Beyond Countable Infinity▶︎ watch 16:44 · read ↗︎
Dialogue Concerning Two New Sciences
“figures in Galileo's work, particularly in his dialogues between Salviati and Simplicio in the, Dialogue Concerning Two New Sciences in 1638. But, actually, I wanna go much further back and talk…” (Joel David Hamkins)
Lectures on Infinity · Lecture 6: Galileo's Paradox of Infinity▶︎ watch 4:08 · read ↗︎
Dialogues Concerning Two New Sciences
“Two New Sciences a wonderful criticism of this whole manner of thinking about giants, and Galileo argued that giants are actually impossible. Physics cannot work like that. The whole idea of a giant” (Joel David Hamkins)
Lectures on Infinity · Lecture 3: The Paradox of Giants: Strange Consequences in High Dimension▶︎ watch 1:54 · read ↗︎
diatribes versus dialogues
“to use the Greek word. Diatribes versus dialogues. So a diatribe or a controversy, in this translation, is when you're just trying to win a debate by any means necessary. This is sort of what we see…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 2: When Every Perception is True▶︎ watch 43:34 · read ↗︎
different species
“have recognized the 15-year-old self. I mean, between 10 and 15, if you passed puberty, you practically became a different species. You developed a whole new sense. You saw a whole new dimension of…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Recap: Making Your Beliefs Your Own▶︎ watch 10:45 · read ↗︎
digression
“And Socrates answers, "Well, we appear to. That remark of yours reminds me of an idea that has often occurred to me before, how natural it is that men who've spent a great part of their lives in…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 3: Does Relativism Refute Itself?▶︎ watch 16:46 · read ↗︎
Dijkstra
“We talked about Edsger Dijkstra, who again, did a ton of stuff all over computer science. For example, probably best known for trying to turn programming into more of a science than an art, okay? For…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 14:41 · read ↗︎
Dijkstra's algorithm
“One famous one, and again, to really be, to the driving directions that you get from your phone use ideas on top of this, but the starting point would be something known as Dijkstra's algorithm. It's…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 2: How Algorithms Outsmart Complexity▶︎ watch 45:04 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 3: Easy Problems, Hard Problems▶︎ watch 0:01 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 14:26 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 5: AI, Quantum Computing, and Beyond▶︎ watch 1:34 · read ↗︎
Dirac equation
“to non-relativistic physical systems. In the case of relativistic physical systems, the equations of motion change from the Schrodinger equation to the Dirac equation, what's called the Dirac…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 5: Three Ways to Save Reality▶︎ watch 1:18:43 · read ↗︎
discrete linear order with endpoints
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 4:16
discretely finite
Lectures on Infinity · Lecture 7: What Does Finite Really Mean?▶︎ watch 10:57
disjoint paths
“paths sort of don't overlap with each other, okay? So they'll be known as disjoint paths in a network, okay? And suppose I just wanna know, you show me a network, I have sort of 10 origins, 10…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Lecture 5: AI, Quantum Computing, and Beyond▶︎ watch 27:37 · read ↗︎
distinction between the countably infinite and the uncountably infinite
“between the countably infinite and the uncountably infinite, a profound idea due to Cantor. We'll start with Zeno and the classical ideas of Aristotle and Archimedes, but eventually, we'll move…” (Joel David Hamkins)
Lectures on Infinity · Intro: Infinity Has a Story to Tell▶︎ watch 0:21 · read ↗︎
distinction between the potentially infinite and the actually infinite
“paradox of supertasks, Galileo's paradox, the distinction between the potentially infinite and the actually infinite. Eventually, we'll find the distinction between the countably infinite and the…” (Joel David Hamkins)
Lectures on Infinity · Intro: Infinity Has a Story to Tell▶︎ watch 0:14 · read ↗︎
divergent
“1/2 more, or 2 more, or 5 more, just by doubling the number of terms enough times. So therefore, the harmonic series is famous for being divergent. It does not converge to a finite value, even though…” (Joel David Hamkins)
Lectures on Infinity · Lecture 1: Zeno's Paradox and Infinite Sums▶︎ watch 31:00 · read ↗︎
divisibility of a line segment
“Maybe it makes sense to consider, say, the divisibility of a line segment. So we have some line segment. Then I can divide it in various ways. I could chop it into pieces. Now I've got a division. Or…” (Joel David Hamkins)
Lectures on Infinity · Lecture 5: Potential vs Actual Infinity▶︎ watch 2:05 · read ↗︎
dogmatic
“By dogmatic, what he means is that he had been trusting his reason to be able to accomplish these feats. He had been assuming that he could simply sit in a chair the way Descartes” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 5: Kant Wakes from His Dogmatic Sleep▶︎ watch 4:25 · read ↗︎
dogmatic slumbers
“the events, one of the great events in his life, that he said in his famous phrase in the introduction, to this book, woke him from his dogmatic slumbers. By dogmatic, what he means is that he had…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 5: Kant Wakes from His Dogmatic Sleep▶︎ watch 4:14 · read ↗︎
dominion over the animals
“We are the greatest living being because God gave Adam dominion over the animals, until Darwin took that away in 1859 and said, "No, we're just another animal. We're the hairless apes." And” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 7: Nietzsche's Warning to the Future▶︎ watch 10:52 · read ↗︎
Don Knuth
“Richard Karp, Don Knuth, all of those will appear, sometimes in big roles, sometimes with cameos, in the stories that we have to tell.” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Intro: Computation and Its Limits▶︎ watch 8:15 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 4: Two Worlds We Might Live In▶︎ watch 40:50 · read ↗︎
Donald Knuth
“tweetable number contestSo Donald Knuth introduced a certain notation which is extremely helpful, and it's partaking of some of these ideas, and that's his up arrow notation. So, let's talk about…” (Joel David Hamkins)
Lectures on Infinity · Lecture 4: The Largest Tweetable Number▶︎ watch 24:23 · read ↗︎
double slit experiments
“for predicting the outcomes of experiments, the outcomes of the kinds of experiments that we've been discussing here, these two paths experiments and double slit experiments, and so on and so forth.…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 3: Two Laws That Can't Both Be True▶︎ watch 0:11 · read ↗︎
doubting
“Hume felt that Descartes didn't understand the very thing that he did, which was doubting. Descartes thought he could doubt beliefs when, in fact, we can't doubt some of our beliefs. We cannot doubt…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Recap: Making Your Beliefs Your Own▶︎ watch 2:49 · read ↗︎
Doxa
“What's an example of a somebody... a judgment or it could also be translated as an opinion, a belief, the word is doxa, which is correct or true, but which clearly is not knowledge? I think you could…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 4: The Soul Behind the Senses▶︎ watch 23:34 · read ↗︎
draw the line objection
“Harvey said is, "There's the obvious draw the line objection. So where do we stop having platonic reality in this list of numbers, 2 to the 1, 2 to the 2, 2 to the 3, and so on, up to 2 to the 100?"…” (Joel David Hamkins)
Lectures on Infinity · Lecture 5: Potential vs Actual Infinity▶︎ watch 18:45 · read ↗︎
dream argument
“He wouldn't be going on with this if he didn't have one. The second skeptical argument is a question about dreaming. Okay. I'm looking at my hand, and I really, really believe that my hand is here.…” (Lee Braver)
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 1: Descartes Reboots Everything▶︎ watch 24:02 · read ↗︎
From Descartes to Nietzsche: The Birth of Science and the Death of God · Lecture 2: The Birth of Modern Science▶︎ watch 31:58 · read ↗︎
dream solution
“and false in other conceptions. There's a certain kind of strategy for solving the continuum problem, the dream solution. This is what many set theorists hope for. What they want to find is a certain…” (Joel David Hamkins)
Lectures on Infinity · Lecture 10: Set Theory's Deepest Mystery▶︎ watch 42:46 · read ↗︎
dream theory
“as his dream at 201-E through 202-B. So, the elements, the primary elements of which we” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 5: Defeat as Philosophical Victory▶︎ watch 18:29 · read ↗︎
dreams
“to the idea that knowledge is perception. These are at 157e. "The question of dreams and of insanity and other diseases and mishearing and seeing and other cases of misperce- misperception." It seems…” (Richard Polt)
Plato’s Theaetetus: An Inquiry into Knowledge · Lecture 2: When Every Perception is True▶︎ watch 29:32 · read ↗︎
driving directions
“for you, that would be one example of technology based on clever algorithmic shortcuts. And for an even more basic example, right, think about just literally multiplying two numbers together, right?…” (Tim Roughgarden)
Computation as a Universal and Fundamental Concept · Intro: Computation and Its Limits▶︎ watch 1:55 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 2: How Algorithms Outsmart Complexity▶︎ watch 30:44 · read ↗︎
Computation as a Universal and Fundamental Concept · Lecture 3: Easy Problems, Hard Problems▶︎ watch 0:00 · read ↗︎
dualism
“that's understandable to see how they got there, they're suddenly getting involved with speculations about, about dualism, about the difference between mind and body, so on and... It's amazing that…” (David Albert)
Quantum Mechanics and the Crisis of Scientific Realism · Lecture 3: Two Laws That Can't Both Be True▶︎ watch 42:23 · read ↗︎