PHL312 Philosophy of Computers and Computation
Classroom: MCC232
Professor: Craig DeLancey
Office: MCC212A

Past Assignments
27 January
Hi, sorry, I have to move my office hours a little bit. I hope that's OK. Today they'll be 10:30 am till 12:00 pm. Here's the link:
28 January
Read the section of the paper "Analog and Analog" called "Digital." This is pages 213-219. The section "analog" is recommended but optional. The paper is on BlackBoard.
4 February
Class will be online. Here is the link:

We'll discuss TMs a bit more, and look forward to our first puzzle (semantics).
7 February
Before class, please read "The Chinese Room" paper (which is actually titled "Minds, Brains, and Programs.") It is on BlackBoard. Read at least the first 5 pages before class; if you're swamped you can finish the rest before Wednesday (the whole paper is just 13 pages long--the rest is notes etc.)
8 February
Apologies! I have conflicts today and will have to move my office hours to Wednesday (which will then at least be in person!). I hope that's OK! Email me if you want to talk today, though, and I can make some time between appointments!
9 February
Before class, finish Searle's "Chinese Room" paper.

We'll discuss the Chinese Room Thought Experiment some more, and we may peek ahead to the frame problem.

Please take a look at Tursi. On the jar download, you should be able to download a copy of the program. Please do see if it will run on your preferred machine.

Office Hours: I will have office hours in my office from 3:00 - 4:30. First in-person hours! Sorry I have too many meetings.
10 February
Office hours 9-11 are at:
11 February
Please read "Cognitive Wheels" by Dan Dennett. It's on BlackBoard. I'll post some study questions for you later today.
14 February
Reading: read parts 1-3 of Turing's "Computing Machinery and Intelligence." Please read part 6 before Wednesday, but it'll be great if you read it before Monday. A version is available here. Parts 4 and 5 are optional. I have also put a copy on BlackBoard. What does Turing mean by "the imitation game"? Be able to describe it. Here are some other question to think on while you read:
  1. Why does Turing want to avoid trying to define intelligence? What challenges do you think that there might be to defining "intelligence"?
  2. Describe the imitation game (now called the Turing Test).
  3. What does Turing mean by "machine"?
16 February
If you cannot run Tursi, you could write the Turing machine "in your head." Tursi helps us to test program, and can prevent you from making some mistakes, and it lets you "watch" a turing machine running; but it should be possible to write the program as we did in class. In such a case, if it is more convenient for you, you could write the machine on paper and hand the paper in to me.

Homework: making two Turing machines. You may work in teams of 3 or fewer people. What you hand in will be two (or three) text files. In the comments section, include the team members and also how the tape must be prepared. (Some people are confused about this. A text file is a kind of file--Word files and rtf files will not open in Tursi. In Word, choose "save as" and then choose "text" to make a text file. If you are confused, email me.)

Thus, your text file can begin with something like:
# My team includes: Craig DeLancey
# This addition machine adds two numbers represented in unary
# as a series of 1s, separated by a single space. The machine
# starts on the leftmost 1 of the left number. The machine ends
# under the the rightmost 1 of the answer number.
#! start 0
#! end H
The first five lines are comment lines. They tell who is on the team and also how the tape must be prepared and how to find the answer. The sixth line specifies that the start state will be 0. The last says that the halting state will be H. You can of course choose your own symbols for start and halt states. Below all that, you list the rules.

You are only handing in this text file; or, if you do the program by hand, then you can just hand in your code written out on a page. The Tursi program is just to test your program. You don't write inside the Tursi program--except to put something on the tape that you can test.

(Here is the simple example we made together in class. Look at it for a model.)

The machines you make will be:
  • a machine to tell if any given number is evenly divisible by three.
  • an addition machine that can handle zero (n+0 or 0+n)
  • Extra credit for the maniacs among you: write a multiplication machine.
EMAIL your files to me. That way, I can load them up myself. Please name your text file "LASTNAME.1.txt" and "LASTNAME.2.txt". If you are a team, just pick one last name. I just need to be able to keep them separate from other people's homework, so this is important.

I was asked for some advice on a few things.
  • It's best if the answer is on the tape (as opposed to saying the answer is in the state of the machine itself). You can say how the answer is put on the tape.
  • You can use whatever tape alphabet you want! You are not limited to 0 and 1!
  • A common error is to give the machine conflicting messages. This will be rejected by Tursi. The whole point of the machine having internal states is so that you can do different things when handling the same input. Suppose sometimes you want the machine to write 1 when reading 0, and sometimes sometimes you want the machine to write 0 when reading 0. You cannot say:
    1 1 1 R 1
    1 1 0 R 1
    That's contradictory. Consider instead:
    1 1 1 R 1
    2 1 0 R 1
18 February
Class is online today. Here's the link for class: .

Office hours online from 3:00 - 4:30 pm, here's the link:
28 February .

2 March
Please read before class: Sprevak's review of the "triviality" arguments before class. We'll discuss this in the next several classes.

Zach sent a link to this video: We're Building Computers Wrong (for artificial intelligence) . The question that our critics raised was: can you send arbitrary messages efficiently in this way? Can you control errors with an analog coding? (Remember our case of: counting a deck of cards versus measuring the height of a deck of cards.)
3 March
Office hours 2-4 pm at:
4 March
Complete and hand in the simple handout of a homework on DFAs that I gave you.

For those of you still looking for a Turing Machine simulator, here is one that seems to work in most browsers. It orders the table columns differently but is otherwise the same (that's not a significant change.) Play with it to get an idea of how the Turing Machine works!
23 March
Reading: Before class, read the short selection from Kripke, available now on BlackBoard. Read pages 6-22. Answer the questions on BlackBoard about the reading.

We are turning now to our last philosophical puzzles:
  1. Philosophical Puzzle 4: what counts as an algorithm? Do algorithms exist independently of their implementations? Can algorithms act on the world? The Kripkenstein paradox for machines. The paradox of infinite cases. The argument that algorithms are irreducible
  2. Philosophical Puzzle 5: Information again; Vitalist problem; Knowledge as independent information; memes.
  3. Philosophical Puzzle 6: The simulation argument. Are we living in a simulation?
  4. Philosophical Puzzle 7: Are simulations “real”?
  5. Philosophical Puzzle 8: Are you a bad person if you do bad things in a simulation?
  6. Philosophical Puzzle 9: Is computer science a science?
We'll have a few fun readings for each of these.
March 24
Office hours today must start and end an hour earlier. Sorry for the inconvenience. Here is the link:
25 March
Reading: Before class, read the short selection from Kripke, available now on BlackBoard. Read pages 32-44. Recommended is 22-32 and also 44-54, but I know you are busy!

Assignment: Short paper (3-4 pages, double spaced, 1" margins) due on one of the following questions:
  • Is Searle right that a machine with only syntax at its disposal cannot manage to have meaning? Very briefly explain his thought experiment. If you disagree with him, what error does he make? (For example, is meaning just syntax? Or can we make meaning with syntax alone?) If he's right, what do you think this meaning thing is such that the isolated algorithm running lacks it?
  • Is the Frame Problem solved by meaning? That is, are we able to avoid (superficially, at least) the Frame Problem by having these things meanings at our disposal? How does that work? If we don't have them, then what if anything seems to distinguish us from the machines falling to the problem?
  • What is the solution to the "every rock is running PowerPoint" problem? Is it a problem (that is, maybe it's ok that every rock is running PowerPoint)? What is your solution to the problem?
Please use my Analytic Philosophy Paper format.
28 March
Recommended watch: before reading the Hofstadter, it will be helpful to watch this goofy fun video:

Reading: before class read the selection from Hofstadter. This is available on BlackBoard.

Practice: Answer the question on BlackBoard about the reading.

This may seem unrelated to our Kripkenstein reading. However, note that the question here is: are algorithms things that have effects in the world, that we need to explain the world, and therefore perhaps about which we should be realists? In a funny way, this is the mirror image of the Kripkenstein problem. It also is essential to a question we will ask later: is computer science a science? Or is it something that could be replace by physics, only we're too lazy to do that?
29 March
I'll have office hours in my office (MCC212A) from 11:30 am -2:30 pm.
1, 4 April
Reading: before class read the simulation argument by Bostrom.

Practice:: answer the questions on BlackBoard about the Bostrom paper, meant to help you think about its argument.

A note about grading. We originally had in the syllabus that we would have a midterm and a final. Since we're considering making this a writing class, I think the two short papers can count as our primary assignments, but we can have a short final where I give you the questions before-hand in order to study.
5 April
Office hours 9:00-11:00 am at .
6 April
Quest. There's a philosophy session from 11:00 - 12:00 in MCC210. Two members of our class are speaking, why not join us for an hour!

I will have in-person office house in MCC212A from 1-3 pm. This will be instead of my Thursday office hours.
11 April
Reading: before class read the selection from Chalmers.
12 April
My office hours need to be later today, sorry. They're 11:00 am - 12:30 pm at: .
13 April
We'll continue our discussion of: are simulations real? And, we may turn to: does what happens in a simulation matter?
14 April
Office hours 2-4 at:

The philosophy club will meet at 5:30pm to watch an episode of Black Mirror called "Nosedive" in MCC room 242. The episode focuses on what social media and the quest for popularity and social acceptance can do to people. Room TBA.
18-22 April
I'll be in Arizona giving a talk and attending talks at a conference. We'll have some asynchronous online classes this week! Our themes will be: does what happens in a simulation matter? Watch my online lecture on a basic question regarding simulations. Then, complete one (just one) of the following tasks; answer the one question on BlackBoard about the reading or film you chose (I list the questions also below).
  • (This one is a little disturbing; skip it if you want to avoid some disturbing content.) Read The Nether, which is on BlackBoard. Did the Nether do a kind of harm? If so, what kind of harm? Explain it. Should the Nether have been shut down? Why? Be very careful to clarify the status of the harm (if any) that was committed; what kinds of things were harmed, for example, if anything?
  • Watch The Matrix, if you haven't done so and if you have access to a copy (the library used to have one but seems to have lost it; sorry). Consider the scene from 1:41:00 to 1:44:15; this scene is here. What did Neo and Trinity just do? Was it morally justified? Explain why or why not. Be very careful to clarify the status of the harm (if any) that was committed; what kinds of things were harmed, for example, if anything?
  • Watch Ready Player One. The library has a copy at PN1997.2 .R43 2018, you can get headphones and watch it there, if you've not see it. The protagonist Wade has two lives or locations: online, and the actual world. It looks like Wade is going to spend much of his life (at least 5/7ths!) in the simulation. Is this a mistake? Is he wasting this portion of his life because the simulation doesn't matter? Or do his life and his accomplishments in the simulation have as much value as his life and accomplishments in the actual world? What if he spent all his time in the simulation? Would that be a good life?
25 April
In class, we will do 3 things:
  1. Discuss your thoughts from our assignment; can virtual environments matter?
  2. I think we should review the Halting Problem, and I'll show you Deutsch's proof that there exist CantGoTu environments.
  3. We can begin our discussion of memes, perhaps with a little historical discussion of vitalism and genocentrism.
I'll have office hours in my office MCC212A from 3:00 -- 4:00 pm.
26 April
Office hours online 9-11 am at: .
27 April
Reading: before class read the selection from Dawkins. This is available on BlackBoard.

Very Unserious Assignment: bring an example of your favorite meme to class.
29 April
Reading: I'll bring you a handout about the Popperian view.
4 May
Read the first four pages of the Clark and Chalmers handout. We'll discuss: can computation extend beyond the computer? Then we'll turn to our last question: is computer science a science?
6 May
We'll continue with our last topic: is computer science a science? Then we can review the entire class in a breathless rush.

Recommended reading: on Blackboard are a few pages from Rapaport on the nature of science and computer science. I recommend you read them before class--it's very straightfoward, easy read, like a well-written news article almost!