If you could give Turing machines one bonus feature, what would it be?

I like to give students the opportunity to be creative. Partially this is because I am noble and committed to good pedagogy practices and all that; partly it is for my own amusement. (Students had to create Twitter bots for my amusement, too --- you can see them here, Twitter login required.)

If you could give Turing machines one bonus feature, what would it be?

Some people were practical:

• I would add a more streamlined ability to count.
• Ctrl-F find value
• Writing proofs for me.
• remember marked spot (instead of needing to mark)
• Its head can go to any position on the tape instantly without having to step through the middle steps.
• to be able to jump to a location in the tape not right next to where the head is

Others were silly:

• snack dispenser
• a cool spoiler (illustration below)

• funny hats (illustration below)

• dance a jig

Some were infeasible:

• Always halt for every problem. [editor's note: provably impossible, you impertinent youth!]

And some were downright haunting:

• Express feelings. It would be nice to know how TM feels when in runs forever. Would it be sad? happy? bored? [editor's note: how would the TM know it is running forever? it could just be churning and doing real computation...]
• consciousness

By far the one that struck the deepest chord and has followed me, hounding me into my dreams, was: "teeth." Yikes.

This post's theme word is stenophagous (adj), "feeding on a limited variety of food." The zookeeper found the dietary needs of TMs a challenge; they were among the most stenophagous charges at the mathematical-hypothetical petting zoo.

Don Giovanni

Opera Philadelphia's production of Don Giovanni offers a very minimal staging and scenery; the stage is draped, from the high ceiling to just above head height, with shimmering golden curtains. Between the curtains and the floor, a bevvy of upright pianos ring the stage. Throughout the production, these pianos were wheeled across the stage and served as scenery, as prop storage, as trees in the garden, as indoor furniture, as walls, and as miscellaneous stationary objects to swoon against.

The performance was lovely and the music was as melodic, and crunchy, and satisfying as Mozart always is. But the plot was inescapably gross, as it centers on a serial sex offender who won't take "no" for an answer and whose every action is manipulative and dismissive of other people. It's hard to see the plot in any other light, and even the mild opera-style staging of the scenes made my skin crawl, as Don Giovanni continually pressed against women and called to them from across the stage and in every way maneuvered the people around him to match his will.

(I recently sat in on some interesting lectures re: Don Giovanni, so I recognize that even at the time it was composed, part of the point of the plot was how noblemen could manipulate people of lesser status in this way. Thanks, Prof. Blasina, for letting me crash your class!)

... and so it was satisfying enough, I suppose, that in the final scene, Don Giovanni is literally dragged to hell, though my reasons for wishing him ill may have differed from original audience's reasons. But overall I'm surprised that this opera continues to be the most-performed opera in the world; perhaps momentum will take it awhile to lose that status? In any case, I've seen it several times now and don't feel any desire to ever see it again.


This post's theme word is nuncupate (v tr), "to solemnly pronounce," or "to declare a will orally." She resolved and nuncupated, and only listened to the audio for evermore.

What is the title of your autobiography?

I take attendance by having the students answer a question.

What is the name of your autobiography?

I've edited to remove students' names; this means some titles are fully expurgated, since a lot of people were not satisfied with a byline and needed to include their name in the title of their own autobiography:

• [name]'s shared thoughts
• My autobiography
• [name]? More like [pun on name]
• [joke about first name]
• [joke about last name and studiousness]
• [pun about name]
• [joke about name's pronunciation]
• [name]'s book

Only one person self-aggrandized with "A Great American Novel"; many people went the other direction:

• Why am I like this
• I wrote some words here
• That Berpy Specy Person
• I smell
• a guy does stuff and has fun (maybe)

Some people only loosely followed the prompt, and their replies mostly reflected what they were thinking about during this lecture on Turing machines and finite automata:

• Am I a finite automaton? Why I'm so forgetful??
• I should NEVER have taken 5 classes in one semester
• TM: Nobody wants ALL The Details

Several students's titles followed a theme:

• How to sleep + eat a ton
• How to sleep more + eat a sh*t ton
• How I sleepwalked through life
• Life Goal: sleep like a kindergarten kid

The cutest one by far was today's winner: Existential Mathematician: Always Looking for "y". (To see previous students' replies to this question, go here.)

This post's theme word is lection (n), "a version of a text in a particular copy or edition; a selection read in a religious service (aka a pericope)." The second printing lection of my autobiography contained a number of typos; the publisher would like to apologize for the particularly egregious typos on the cover, including the author's name.