Danny Hillis, et al

[The article reproduced hereafter is in the public domain.]

ko·an, n.  [koh, public + an, matter]  A puzzling, often paradoxical statement or story, used in Zen Buddhism as an aid to meditation and a means of gaining spiritual awakening. Their purpose is to help one to enlightenment by temporarily jamming normal cognitive processing so that something more interesting can happen. Hackers are very fond of the koan form and compose their own koans for humororous and/or enlightening effect.

The AI Koans below are examples of a genre of jokes told at the MIT AI Lab about various noted hackers. This series of pastiches of Zen teaching riddles were originally composed by Danny Hillis, who would later found Connection Machines, Inc. In reading these, it is at least useful to know that Minsky, Sussman, and Drescher are AI researchers of note, that Tom Knight was one of the Lisp machine's principal designers, and that David Moon wrote much of Lisp Machine Lisp.

Knight and the Lisp machine

A novice was trying to fix a broken Lisp machine by turning the power off and on.

Knight, seeing what the student was doing, spoke sternly: "You cannot fix a machine by just power-cycling it with no understanding of what is going wrong."

Knight turned the machine off and on.

The machine worked.

Moon instructs a student

One day a student came to Moon and said, "I understand how to make a better garbage collector. We must keep a reference count of the pointers to each cons."

Moon patiently told the student the following story: "One day a student came to Moon and said: I understand how to make a better garbage collector..."

Note: Pure reference-count garbage collectors have problems with circular structures that point to themselves.

Sussman attains enlightment

In the days when Sussman was a novice, Minsky once came to him as he sat hacking at the PDP-6.

"What are you doing?", asked Minsky.

"I am training a randomly wired neural net to play Tic-Tac-Toe.", Sussman replied.

"Why is the net wired randomly?", asked Minsky.

"I do not want it to have any preconceptions of how to play", Sussman said.

Minsky shut his eyes.

"Why do you close your eyes?", Sussman asked his teacher.

"So that the room will be empty."

At that moment, Sussman was enlightened.

Greenblatt sticks it in

A student, in hopes of understanding the Lambda-nature, came to Greenblatt. As they spoke a Multics system hacker walked by.

"Is it true", asked the student, "that PL-1 has many of the same data types as Lisp".

Almost before the student had finished his question, Greenblatt shouted, "FOO!", and hit the student with a stick.

Drescher and the toaster

A disciple of another sect once came to Drescher as he was eating his morning meal.

"I would like to give you this personality test", said the outsider, "because I want you to be happy.

" Drescher took the paper that was offered to him, put it into the toaster, and said:

"I wish the toaster to be happy too."

Knuth on a pilgrimage

A man from AI walked across the mountains to SAIL to see the Master, Knuth. When he arrived, the Master was nowhere to be found.

"Where is the wise one named Knuth?", he asked a passing student.

"Ah," said the student," you have not heard. He has gone on a pilgrimage across the mountains to the temple of AI to seek out new disciples."

Hearing this, the man was Enlightened.

The Lisp Hacker and the Undergraduate

A famous Lisp Hacker noticed an Undergraduate sitting in front of a Xerox 1108, trying to edit a complex Klone network via a browser.

Wanting to help, the Hacker clicked one of the nodes in the network with the mouse, and asked "what do you see?"

Very earnesty, the Undergraduate replied "I see a cursor."

The Hacker then quickly pressed the boot toggle at the back of the keyboard, while simultaneously hitting the Undergraduate over the head with a thick Interlisp Manual.

The Undergraduate was then Enlightened.

The Tao of Programming

A master was explaining the nature of Tao to one of his novices.

"The Tao is embodied in all software - regardless of how insignificant," said the master.

"Is Tao in a hand-held calculator?" asked the novice.

"It is," came the reply.

"Is the Tao in a video game?" continued the novice.

"It is even in a video game," said the master.

"And is the Tao in the DOS for a personal computer?"

The master coughed and shifted his position slightly. "The lesson is over for today," he said.