Why MIT switched from Scheme to Python (2009) • Hacker News Board

Re: Why MIT switched from Scheme to Python (2009)

#151

Post by swannodette » Fri, Jul 25, 2025, 10:40 PM UTC

kragen wrote: post #149

zahlman wrote: post #125

Earlier quoted context omitted.

> There were four 15-unit courses, each about one of these "languages": The description you offer is strange to me. The Lisp family of languages are multi-paradigm (arguably paradigm-independent) and can hardly be called "procedural". The core material of SICP revolves around considering the "means of combination" and "means of abstraction" offered by a programming language — concepts that sound to me like they have…

SICP is fundamentally about the notion that programs are primarily a means of communication between people, being written by people for other people to read, and only secondarily a thing for computers to execute. And it really opened my eyes to the landscape of programming paradigms that exist—indeed, it continues to do so! But your comment is completely off-base. In Circuits and Electronics, as I understand it, the…

> Following SICM I think even its authors were doubtful about whether Scheme was a good medium for working with those ideas.

Hrm https://mitp-content-server.mit.edu/books/content/sectbyfn/b...

Re: Why MIT switched from Scheme to Python (2009)

#152

Post by gowld » Fri, Jul 25, 2025, 10:57 PM UTC

zozbot234 wrote: post #119

MontyCarloHall wrote: post #14

Isn't this just part of the broader trend of CS departments switching away from teaching computer science to teaching computer engineering, which in turn is part of the more general trend of colleges becoming more vocational? LISP dialects like Scheme are excellent for teaching pure computer science because they are the closest thing to executing lambda calculus expressions. Whereas Python is excellent for teaching a…

> Whereas Python is excellent for teaching applied computer engineering, because it's essentially executable pseudocode for imperative languages It's not that simple, Python is a fiddly, complex, high-level language that has accreted features in a very ad-hoc way. This makes it very hard to teach and learn in a way that's expected to pay even the most cursory attention to actual rigor. You could probably define a Bab…

Python was invented as a language for newbies. It's come a long way!

https://en.wikipedia.org/wiki/History_of_Python#Version_1

> During Van Rossum's stay at CNRI, he launched the Computer Programming for Everybody (CP4E) initiative, intending to make programming more accessible to more people, with a basic "literacy" in programming languages, similar to the basic English literacy and mathematics skills required by most employers. Python served a central role in this: because of its focus on clean syntax, it was already suitable, and CP4E's goals bore similarities to its predecessor, ABC.

https://en.wikipedia.org/wiki/ABC_(programming_language)

> It is intended for teaching or prototyping

Re: Why MIT switched from Scheme to Python (2009)

#153

Post by gowld » Fri, Jul 25, 2025, 10:59 PM UTC

darksaints wrote: post #46

MontyCarloHall wrote: post #14

Isn't this just part of the broader trend of CS departments switching away from teaching computer science to teaching computer engineering, which in turn is part of the more general trend of colleges becoming more vocational? LISP dialects like Scheme are excellent for teaching pure computer science because they are the closest thing to executing lambda calculus expressions. Whereas Python is excellent for teaching a…

Colleges becoming more vocational is a consequence of colleges becoming more expensive for students. If you are paying all of that money for college, you better get a good job out of it. I don't see that as a bad thing necessarily, but it would definitely be nice if we had better paths for those who want to end up in research. I'd argue that SML (or derivative thereof) would make for a better teaching language, for b…

College becoming more vocatioanl is a consequence of colleges becoming more accessible to a much larger population, beyond the already wealthy.

Community colleges are the cheapest colleges, yet the most vocational.

The most expensive colleges are the Liberal Arts Colleges and the Ivy League, which are the least vocational.

Re: Why MIT switched from Scheme to Python (2009)

#154

Post by ggm » Fri, Jul 25, 2025, 11:14 PM UTC

keithwinstein wrote: post #75

This story has been reposted many times, and I think GJS's remarks (as recorded by Andy Wingo) are super-interesting as always, but this is really not a great account of "why MIT switched from Scheme to Python." Source: I worked with GJS (I also know Alexey and have met Andy Wingo), and I took 6.001, my current research still has us referring to SICP on a regular basis, and in 2006 Kaijen Hsiao and I were the TAs for…

A useful reminder that economics plays as much, if not more import in what is taught and how it is taught, as any pedagogical drive. If attendance drops, universities can pivot. Gotta get the bums on seats.

20 years ago Cisco came shopping in Australia for ee grads who could do microcode. The US degree mills had stopped teaching students how to code an edge case for most jobs, and the router and switch vendor had to find places who still did that.

Re: Why MIT switched from Scheme to Python (2009)

#155

Post by zahlman » Fri, Jul 25, 2025, 11:24 PM UTC

kragen wrote: post #149

zahlman wrote: post #125

Earlier quoted context omitted.

> There were four 15-unit courses, each about one of these "languages": The description you offer is strange to me. The Lisp family of languages are multi-paradigm (arguably paradigm-independent) and can hardly be called "procedural". The core material of SICP revolves around considering the "means of combination" and "means of abstraction" offered by a programming language — concepts that sound to me like they have…

SICP is fundamentally about the notion that programs are primarily a means of communication between people, being written by people for other people to read, and only secondarily a thing for computers to execute. And it really opened my eyes to the landscape of programming paradigms that exist—indeed, it continues to do so! But your comment is completely off-base. In Circuits and Electronics, as I understand it, the…

> But your comment is completely off-base.

I think it is rather your reply that is off-base; or else I have not made myself sufficiently clear.

My point was simply that the words used to describe the other courses are better fits for what SICP teaches than "procedural", which is a poor fit for describing Lisp-family languages and would make more sense applied to other contemporary languages like COBOL and FORTRAN (and of course typical Algol-family languages).

I understand perfectly well what "functional" means in the context of signals and systems. I took such a course in undergrad, 20+ years ago. But I was using abstract nouns there, rather than adjectives (and writing "function" rather than "functionality" would not really have resolved the issue).

The material in SICP deeply explores the functional programming idiom. A big part of the point of using a Lisp dialect is that functions are first-class (I've watched the OCW lectures; there's a whole section discussing what that means and entails) objects, which enables higher-order functions.

Nothing in my comment is about modelling anything to do with electronics in software.

Re: Why MIT switched from Scheme to Python (2009)

#156

Post by josh2600 » Fri, Jul 25, 2025, 11:31 PM UTC

aleph_minus_one wrote: post #96

keithwinstein wrote: post #75

This story has been reposted many times, and I think GJS's remarks (as recorded by Andy Wingo) are super-interesting as always, but this is really not a great account of "why MIT switched from Scheme to Python." Source: I worked with GJS (I also know Alexey and have met Andy Wingo), and I took 6.001, my current research still has us referring to SICP on a regular basis, and in 2006 Kaijen Hsiao and I were the TAs for…

Thanks for this detailed explanation. A semi-off-topic side question: > the students were supposed to each get a software radio and build a Wi-Fi-like system (the software radios proved difficult and, much later, I helped make this an acoustic modem project). What was the reason why the software radios proved difficult?

Not OP but in general sourcing software and hardware radios in that time was very difficult. There weren’t good open-source implementations and everything had to be sorta reverse engineered which meant that anyone with the skill to do that was selling it for a lot of dollars.

Source: did 10 years in telecom land.

Re: Why MIT switched from Scheme to Python (2009)

#157

Post by cactusfrog » Fri, Jul 25, 2025, 11:40 PM UTC

varenc wrote: post #11

I was one of the last batches of students on the old Scheme curriculum. I absolutely loved it! Understanding that all loops could be done via recursion, and what a side effect is, is what fundamentally made me fall in love with CS. I've heard good things about the new, and now newer, curriculum but I know I wouldn't have had the awakening I did if it weren't for scheme. RIP SICP --- ps another fun story: we had some…

I worked an MIT programmer who bragged about the Scheme curriculum. He was also the worst programmer that I’ve worked with. He really liked clojure and would constantly complain about Python syntax, and ended up quitting abruptly when his hand spun Datomic based system was rejected.

I think there is a trap in thinking that a strange way of being taught puts one at an advantage. It is really annoying to work with people who believe they are more enlightened than others.

Re: Why MIT switched from Scheme to Python (2009)

#158

Post by globalnode » Fri, Jul 25, 2025, 11:52 PM UTC

amirhirsch wrote: post #150

keithwinstein wrote: post #75

This story has been reposted many times, and I think GJS's remarks (as recorded by Andy Wingo) are super-interesting as always, but this is really not a great account of "why MIT switched from Scheme to Python." Source: I worked with GJS (I also know Alexey and have met Andy Wingo), and I took 6.001, my current research still has us referring to SICP on a regular basis, and in 2006 Kaijen Hsiao and I were the TAs for…

Hi Keith! Another consideration was that the core computer programming skills needed to be taught more broadly to basically everyone and not just course 6 students. Source: I shared an office with Keith next to Hal and Gerry--he taught me Java! Fun anecdote: we had to move RMS's stuff to the new CSAIL building because he had broken his arm punching a wall.

Ive broken my hand punching a wall, its not nice :/. Also I hated scheme in first year uni, my brain just did not get the pattern matching required... Australian uni's probably just copied the syllabus from US ones at that time.

Re: Why MIT switched from Scheme to Python (2009)

#159

Post by Jtsummers » Fri, Jul 25, 2025, 11:55 PM UTC

zahlman wrote: post #155

kragen wrote: post #149

Earlier quoted context omitted.

SICP is fundamentally about the notion that programs are primarily a means of communication between people, being written by people for other people to read, and only secondarily a thing for computers to execute. And it really opened my eyes to the landscape of programming paradigms that exist—indeed, it continues to do so! But your comment is completely off-base. In Circuits and Electronics, as I understand it, the…

> But your comment is completely off-base. I think it is rather your reply that is off-base; or else I have not made myself sufficiently clear. My point was simply that the words used to describe the other courses are better fits for what SICP teaches than "procedural", which is a poor fit for describing Lisp-family languages and would make more sense applied to other contemporary languages like COBOL and FORTRAN (an…

You may want to take your issue with the use of the word "procedural" up with the authors of SICP:

> Underlying our approach to this subject is our conviction that “computer science” is not a science and that its significance has little to do with computers. The computer revolution is a revolution in the way we think and in the way we express what we think. The essence of this change is the emergence of what might best be called procedural epistemology—the study of the structure of knowledge from an imperative point of view, as opposed to the more declarative point of view taken by classical mathematical subjects. Mathematics provides a framework for dealing precisely with notions of “what is.” Computation provides a framework for dealing precisely with notions of “how to.” [Emphasis in original]

-- Preface to the First Edition

Re: Why MIT switched from Scheme to Python (2009)

#160

Post by kokx » Fri, Jul 25, 2025, 11:58 PM UTC

kstrauser wrote: post #40

90s_dev wrote: post #35

Earlier quoted context omitted.

To be fair, if you learn computer science well enough to thoroughly understand Scheme, I don't think it'll take more than a few weeks during the summer to learn Python.

I disagree. You can learn the language itself pretty quickly. Finding your way through the expansive standard library will take longer. Getting a good handle on the package ecosystem is a lifetime learning project.

This depth you are never going to get in a college education anyway. Especially not since programming isn't (and shouldn't be) the only thing you learn in a Software Engineering / Computer Science bachelor.