The Sussman Anomaly

MIT computer scientist Gerald Sussman offered this example to show the importance of sophisticated planning algorithms in artificial intelligence. Suppose an agent is told to stack these three blocks into a tower, with A at the top and C at the bottom, moving one block at a time:

https://commons.wikimedia.org/wiki/File:Sussman-anomaly-1.svg
Image: Wikimedia Commons

It might proceed by separating the goal into two subgoals:

  1. Get A onto B.
  2. Get B onto C.

But this leads immediately to trouble. If the agent starts with subgoal 1, it will move C off of A and then put A onto B:

https://commons.wikimedia.org/wiki/File:Sussman-anomaly-2.svg
Image: Wikimedia Commons

But that’s a dead end. Because it can move only one block at a time, the agent can’t now undertake subgoal 2 without first undoing subgoal 1.

If the agent starts with subgoal 2, it will move B onto C, which is another dead end:

https://commons.wikimedia.org/wiki/File:Sussman-anomaly-3.svg
Image: Wikimedia Commons

Now we have a tower, but the blocks are in the wrong order. Again, we’ll have to undo one subgoal before we can undertake the other.

Modern algorithms can handle this challenge, but still it illustrates why planning is not a trivial undertaking. Sussman discussed it as part of his 1973 doctoral dissertation, A Computational Model of Skill Acquisition.

| Science & Math

Entre Nous

https://archive.org/details/strand-1897-v-14/page/690/mode/2up?view=theater

In 1896 the letter above arrived at the New York post office. As there was no Goat Street in New York, the office marked it misdirected and sent it on to Washington, where clerks eventually opened it, looking for further clues. They found this:

Dear Santa, — When I said my prayers last night I told God to tell you to bring me a hobby horse. I don’t want a hobby horse, really. A honestly live horse is what I want. Mamma told me not to ask for him, because I probably would make you mad, so you wouldn’t give me anything at all, and if I got him I wouldn’t have any place to keep him. A man I know will keep him, he says, if you get him for me. I thought you might like to know. Please don’t be mad. — Affectionately, John.

P.S. — A shetland would be enough.

P.S. — I’d rather have a hobby horse than nothing at all.

“I am very sorry to say that John did not get the horse,” wrote Mary K. Davis in the Strand. “Little boys who don’t do as their mothers tell them find little favour with Santa Claus.”

| Society

All the Uses of This World

https://commons.wikimedia.org/wiki/File:%C3%9Altima_escena_de_Hamlet,_por_Jos%C3%A9_Moreno_Carbonero.jpg

As a footnote to the above, I would like to say that I am getting very tired of literary authorities, on both the stage and the screen, who advise young writers to deal only with those subjects that happen to be familiar to them personally. It is quite true that this theory probably produced A Tree Grows in Brooklyn, but the chances are it would have ruled out Hamlet.

— Wolcott Gibbs, New Yorker, January 6, 1945

| Literature

In a Word

nimiety
n. superfluity

brachylogy
n. a condensed expression

scrimption
n. a very small amount or degree

perficient
adj. that accomplishes something; effectual

Leonard Bernstein conducts the Vienna Philharmonic without using his hands, 1984:

| Art · Language

The Sandwheel

https://commons.wikimedia.org/wiki/File:Sandwheel.gif

This is a variation on a perpetual motion machine proposed by the Indian mathematician Bhāskara II around 1150. Each of the wheel’s tilted spokes is filled with a quantity of sand. As the tubes descend on the right, the sand within them shifts outward, exerting greater torque in the clockwise direction and thus keeping the wheel turning forever.

Unfortunately the same design ensures that there’s always a greater quantity of sand on the left, so nothing happens.

| Science & Math

Matriarch

https://commons.wikimedia.org/wiki/File:Laysan_albatross_fws.JPG

In 1956, ornithologist Chandler Robbins tagged a wild female Laysan albatross at the Midway Atoll National Wildlife Refuge in the North Pacific. The bird, dubbed Wisdom, went on to a stunning career, flying more than 3 million miles, equivalent to 120 trips around the Earth. She has been seen at the atoll as recently as last December, making her, at 72, the the oldest known wild bird in the world.

In that time she’s hatched as many as 36 chicks, a significant contribution to the struggling wild albatross population. The U.S. Fish and Wildlife Service wrote, “Her health and dedication have led to the birth of other healthy offspring which will help recover albatross populations on Laysan and other islands.” Bruce Peterjohn, chief of the North American Bird Banding Program, added, “To know that she can still successfully raise young at age 60-plus, that is beyond words.”

| Science & Math

Bootstraps

The 45-letter pneumonoultramicroscopicsilicovolcanoconiosis is often cited as one of the longest words in English — it’s been recognized both by Merriam-Webster and by the Oxford English Dictionary. The OED Supplement traced it to a 1936 puzzle book by Frank Scully called Bedside Manna, defining it as “a disease caused by ultra-microscopic particles of sandy volcanic dust.” But in fact it had appeared first in a Feb. 23, 1935, story in the New York Herald Tribune:

Puzzlers Open 103rd Session Here by Recognizing 45-Letter Word

Pneumonoultramicroscopicsilicovolcanoconiosis succeeded electrophotomicrographically as the longest word in the English language recognized by the National Puzzlers’ League at the opening session of the organization’s 103d semi-annual meeting held yesterday at the Hotel New Yorker.

The puzzlers explained that the forty-five-letter word is the name of a special form of silicosis caused by ultra-microscopic particles of silica volcanic dust …

At the meeting NPL president Everett M. Smith had claimed the word was legitimate, but in fact he’d coined it himself. Distinguished by the newspaper, it found its way into Scully’s book and thence into the dictionaries, “surely one of the greatest ironies in the history of logology,” according to author Chris Cole. Today it’s recognized as long but phony — Oxford changed its definition to “an artificial long word said to mean a lung disease caused by inhaling very fine ash and sand dust.”

(Chris Cole, “The Biggest Hoax,” Word Ways 22:4 [November 1989], 205-206.)

| Hoaxes · Language

Invisible Artworks

For his 1959 work Zone de Sensibilité Picturale Immatérielle, Yves Klein sold the ownership of empty space.

In its 1967 Air-Conditioning Show, English conceptual collaborative Art & Language presented an empty room containing two air conditioning units; the artwork was “what is felt and said about it.”

James Lee Byars’ 1969 work The Ghost of James Lee Byars consisted of the emptiness and darkness of a pitch-black room.

Robert Barry communicated his 1969 Telepathic Piece mentally to visitors; the artwork was “a series of thoughts that are not applicable to language or image.”

Andy Warhol’s 1985 Invisible Sculpture was entirely intangible.

Tom Friedman’s 1992 work Untitled (A Curse)” consisted of a region of empty space that had been cursed by a witch.

Roman Ondak’s 2006 work More Silent Than Ever was an empty exhibition room in which a covert listening device had allegedly been hidden; visitors were told they were being monitored, but no evidence was ever given that the device really existed.

Salvatore Garau’s 2021 sculpture Io Sono occupied an area 5 feet square but was otherwise imperceptible.

Ruben Gutierrez’s 2022 work This Sculpture Makes Me Cry (A Spell) was said to represent what the artist could not see but which affected him emotionally.

Warhol and Gutierrez both presented their sculptures on white pedestals. Is there any way to prove they’re not the same piece?

| Uncategorized