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oluckyman

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I was a visiting professor there in 1989, and sat in on the course, which was on math proofs. We had weekly homework, which I did. In one class, I told Dijkstra that his proof was wrong. He couldn’t see my point, and we argued briefly and agreed to disagree. It was the only time anyone spoke up in class without being asked to by Dijkstra. At the start of the next class, Dijkstra announced that his attempted proof was indeed wrong, and proceeded to give a revised proof. Everyone was impressed by his intellectual honesty. He wrote up the episode as EWD 1044 https://www.cs.utexas.edu/users/EWD/transcriptions/EWD10xx/E...

Dijkstra asked me to sit in on one final oral exam which he was expecting to be tricky. It was a very intimidating atmosphere for the student.

From the article:

Dennett models the mind on the idea of the computer. But computers are the products of human designers. Hence it makes no sense to try to explain the mind in terms of computers, since the existence of a computer itself presupposes the existence of a designing mind.

I read no further.

In section III B (p.8) the paper states that “in 1982…Gries[24] devised another linear algorithm” for the maximum subarray problem. I remember that. Jon Bentley visited Cornell, and posed the problem to me and Gries together. We thought on it independently overnight and presented a linear solution to Bentley the next day. Gries had a simpler invariant, and I had simpler code (using min). I never knew he wrote the paper until now, and am not one of the several people he mentions in the Acknowledgement, although he does say “Bentley…challenged US with this problem”.

I'll add my voice to the chorus that says this is a symptom of a more fundamental issue: aphantasia. As a card-carrying aphantasiac, I'm skeptical of the ability of most people to visualize. I recall hearing of an experiment in which people were asked to draw a bicycle from their imagination. The results were laughable, yet, no doubt, the subjects would self report that, sure, they could visualize a bicycle.

It’s helpful, but if the task is to draw the imagined bicycle, then you would presumably add details as far as possible. But for most people the result is very far from what they would draw if a bicycle was in front of them. So what they imagine is not a bicycle. So most people can’t imagine a bicycle.

Then the “images” most people say they can imagine in their “mind’s eye” might be little different from what an aphantasiac like me would produce if asked to draw them. Perhaps I am not missing much at all.

Most people could draw a bicycle well enough while looking at it. But most people are hopeless when asked to draw a bicycle from their imagination. But most people don’t have aphantasia. I do, so am sceptical when people say they can picture a bicycle (say) in their “mind’s eye”.

The commentary misrepresents the original study as much as the popular press coverage it criticizes.

From the Abstract of the study:

“grammar-learning ability...is preserved almost to the crux of adulthood (17.4 years old) and then declines steadily”

“The results support the existence of a sharply-defined critical period for language acquisition”

From the commentary:

“It’s not even true that young children learn languages faster than older children or adults”.

The shining light angle is close to clickbait, since it's presented as a lower-order hack at best. But the article itself is comprehensive and interesting. The focus is on looking for hacks that might work, so medical studies are cherry picked rather than deeply investigated, but that's to be expected. After "lifestyle" advice on diet, sleep, and exercise, creatine supplements were highly recommended.