I consider that I understand an equation when I can predict the properties of its solutions, without actually solving it.

-- Paul Dirac

if we want economics to be a science, we have to recognize that it is not ok for macroeconomists to hole up in separate camps, one that supports its version of the geocentric model of the solar system and another that supports the heliocentric model. As scientists, we have to hold ourselves to a standard that requires us to reach a consensus about which model is right, and then to move on to other questions.

The alternative to science is academic politics, where persistent disagreement is encouraged as a way to create distinctive sub-group identities.

--Paul Romer, NYU, "My Paper “Mathiness in the Theory of Economic Growth”

In 1736 I lost one of my sons, a fine boy of four years old, by the small-pox, taken in the common way. I long regretted bitterly, and still regret that I had not given it to him by inoculation. This I mention for the sake of parents who omit that operation, on the supposition that they should never forgive themselves if a child died under it; my example showing that the regret may be the same either way, and that, therefore, the safer should be chosen.

Ben Franklin

Our ideal in crafting an argument is a skeptical but friendly audience, suitable to the context. A skeptical audience is questioning of our observations, not swayed by emotional appeals, but not so skeptical as to be dismissive. The ideal audience is curious; humble, but not stupid. It is an idealized version of ourselves at our best,

Max Shron, Thinking with Data, O'Reily 2014

It would be nice to think that you can trust powerful people who are aware that power corrupts. But this turns out not to be the case.

• Jon Schwarz, A Tiny Revolution

What I’m objecting to here is the idea—encouraged, I fear, by lots and lots of statistics textbooks, including my own, that you can routinely learn eternal truths about human nature via these little tabletop experiments.

Andrew Gelman, The aching desire for regular scientific breakthroughs

As a rule, news is a distraction from worthy intellectual pursuits.

-- Bryan Caplan, expanded here

I believe in articulate discussion (in monologue or dialogue) of how one solves problems, of why one goofed that one, of what gaps or deformations exist in one's knowledge and of what could be done about it. I shall defend this belief against two quite distinct objections. One objection says: "it's impossible to verbalize; problems are solved by intuitive acts of insight and these cannot be articulated." The other objection says: "it's bad to verbalize; remember the centipede who was paralyzed when the toad asked which leg came after which."

J.S. Bruner tells us (in his book Towards a Theory of Instruction) that he finds words and diagrams "impotent" in getting a child to ride a bicycle. But while his evidence shows (at best) that some words and diagrams are impotent, he suggests the conclusion that all words and diagrams are impotent. The interesting conjecture is this: the impotence of words and diagrams used by Bruner is explicable by Bruner's cultual origins; the vocabulary and conceptual framework of classical psychology is simply inadequate for the description of such dynamic processes as riding a bicycle. To push the rhetoric further, I suspect that if Bruner tried to write a program to make an IBM 360 drive a radio controlled motorcycle, he would have to conclude (for the sake of consistency) that the order code of the 360 was impotent for this task. Now, in our laboratory we have studied how people balance bicycles and more complicated devices such as unicycles and circus balls. There is nothing complex or mysterious or undescribable about these processes. We can describe them in a non-impotent way provided that a suitable descriptive system has been set up in advance. Key components of the descriptive system rest on concepts like: the idea of a "first order" or "linear" theory in which control variables can be assumed to act independently; or the idea of feedback.

A fundamental problem for the theory of mathematical education is to identify and name the concepts needed to enable the beginner to discuss in mathematical thinking in a clear articulate way.

-- Seymour Papert, distinguished mathematician, educator, computer scientist, and AI researcher, in his 1971 essay "Teaching Children to be Mathematicians vs. Teaching about Mathematics".

“Waste no more time arguing about what a good man should be. Be one.”

• Marcus Aurelius

I recommend that before setting out to beat the market, you worry about whether you’ll be able to do as well as the market. The typical investor does worse than the market averages, usually due to buying more when the market is high than when it is low. Take a few minutes to imagine that you will be influenced by the mood of other investors to be pessimistic when the market has been doing poorly, and optimistic when the market has been doing well. Also imagine that you will have more money available to invest when the market is high than when it is low. If you’re confident that you can avoid these problems, please stop reading this post – you’re either good enough to not need my advice, or deluded enough that you ought to start somewhere else.

The efficient market hypothesis is an approximation that is good enough for many purposes, such as telling you that you shouldn’t be confident that you can beat the market by much unless you’ve got a really good track record [1].Many people infer from this that any effort to beat the market will be wasteful. Why do I disagree?The simplest answer is that if there were no inefficiencies in the market, the people who are making the market efficient wouldn’t have incentives to continue doing so.

Diversifying across countries reduces some hard-to-measure risks. One of the most thoughtless mistakes investors make is to invest mostly in stocks of their own country, when it makes more sense to underweight the country whose economy their other income is most correlated with. Betting on one country might make some sense if you have good reason to think it will do better, but you’re more likely to do it for signaling purposes or due to availability bias.

Note that most fund managers are experts at something. But that something is typically some form of “doing what the customer asks”, not beating the market. Amateur investors who try to pay experts to beat the market usually fail by mistaking luck for skill.

-Bayesian Investor Blog

A man who lies to himself is often the first to take offense. It sometimes feels very good to take offense, doesn't it? And surely he knows that no one has offended him, and that he himself has invented the offense and told lies just for the beauty of it, that he has exaggerated for the sake of effect, that he has picked on a word and made a mountain out of a pea -- he knows all of that, and still he is the first to take offense, he likes feeling offended, it gives him great pleasure, and thus he reaches the point of real hostility

"The Brothers Karamazov", Dostoyevsky

I sought good judgment mostly by collecting instances of bad judgment, then pondering ways to avoid such outcomes... I became so avid a collector of instances of bad judgment that I paid no attention to boundaries between professional territories. After all, why should I search for some tiny, unimportant, hard-to-find new stupidity in my own field when some large, important, easy-to-find stupidity was just over the fence in the other fellow's professional territory? Besides, I could already see that real-world problems didn't neatly lie within territorial boundaries. They jumped right across. And I was dubious of any approach that, when two things were inextricably intertwined and interconnected, would try and think about one thing but not the other. I was afraid, if I tried any such restricted approach, that I would end up, in the immortal words of John L. Lewis, "with no brain at all, just a neck that had haired over."

- Charlie Munger (Warren Buffet's partner) in Poor Charlie's Almanack (The Psychology of Human Misjudgment section)

The free-market system has salient flaws and hidden benefits. All other systems have hidden flaws and salient benefits.

Nassim Taleb

The barriers are not erected which can say to aspiring talents and industry, 'Thus far and no farther.'

Ludwig van Beethoven

Literature and Music in the Atlantic World, 1767-1867

I am suggesting that we move too quickly to the view that rationalism is always an assault on the romantic soul, that it is a symptom of anxiety about our own madly passionate natures, or that it is a flight from love. Instead, rationalism may have its adaptive side, one that seeks to reinforce the ego structures needed to experience the passionate intensity of human emotions. It is possible to see rationalism not as an escape from romanticism, not as a defensive maneuver to protect the self from the excesses of desire, but instead as an effort to master, to fully experience, our passionate natures.

-- Anne C. Dailey, in her paper Liberalism's Ambivalence.

Three of the most important [aspects of science] are that (1) science employs methods of systematic empiricism; (2) it aims for knowledge that is publicly verifiable; and (3) it seeks problems that are empirically solvable and that yield testable theories.

Keith E. Stanovich in How to Think Straight About Psychology

In an important sense, scientific knowledge does not exist at all until it has been submitted to the scientific community for criticism and empirical testing by others.

Keith E. Stanovich in How to Think Straight About Psychology