
Brian Harvey: Why SICP matters - gnosis
http://www.eecs.berkeley.edu/~bh/sicp.html
======
fdr
I am one of Brian Harvey's student progeny. I still consider the SICP as my
favorite computer science book, and in retrospect CS61A one of my favorite and
most important courses. There is something amazing about a course that takes
one from "square can be defined as (define (square x) (* x x))" to writing an
interpreter, and be something a mere mortal _can_ work through in a few
months. And that's just chapter one to four out of six in SICP, if memory
serves.

I like Python, and use it in industry. Ruby, Go, and C also. In the past, I
wrote Common Lisp professionally as well. I do not pine for Scheme or CL,
although both had some of their own unique charm. Nevertheless, I think
Brian's sentiments about Scheme's clarity in stripping away what can seem to
be the 'magic' in programming while maintaining an absolutely rigorous
representation that can actually be executed are spot-on. There will be plenty
of time in practical work to reintroduce some magic to make practical tasks
easier, but there is but a precious few years -- or indeed, just a semester --
to examine the structure of abstraction at its very core.

~~~
krickle
I love the story where the creators defined a Lisp interpreter in Lisp, and
then one said, "you know, we don't have a Lisp compiler, but I could compile
this source by hand." It's quite an elegant concept when you accidentally
create a fully-functional interpreter overnight.

~~~
masklinn
The quote:

> Steve Russell said, look, why don't I program this eval..., and I said to
> him, ho, ho, you're confusing theory with practice, this eval is intended
> for reading, not for computing. But he went ahead and did it. That is, he
> compiled the eval in my paper into IBM 704 machine code, fixing bug, and
> then advertised this as a Lisp interpreter, which it certainly was. So at
> that point Lisp had essentially the form that it has today...

a shorter version from "History of Lisp" page 9:

> S.R. Russell noticed that _eval_ could serve as an interpreter for LISP,
> promptly hand coded it, and we now had a programming language with an
> interpreter.

------
chimeracoder
> What MIT decided was to move from a curriculum organized around topics
> (programming paradigms, then circuits, then signal processing, then
> architecture) to a curriculum organized around applications (let's build and
> program a robot; let's build and program a cell phone).

While this is offered as an excuse for switching away from SICP, I don't like
this either.

Programming paradigms are the perfect introduction to programming. First, it
naturally teaches you one of the most fundamental concepts in computer science
(abstraction) by example; with the SICP approach, you learn about abstractions
by constructing your own idioms for abstractions within a programming
paradigm!

Second, applications become easier and easier to develop the more one learns
to break out of a single paradigm and borrow ideas and tools from each as
needed - otherwise, it's easy to get stuck in a rut and miss a simple but
elegant solution to the problem at hand. Being able to cross-pollinate
features or ideas idiomatic in one language to another gives you a Leatherman
instead of an x-acto knife.

Having a fundamental grasp of programming paradigms makes programming
languages feel like a second skin, rather than an obstacle sitting between the
brain and the binary output.

~~~
mcguire
He goes on to write,

" _Perhaps in time the applications-first approach will spark a revolution as
profound as the one that followed SICP, but it hasn't happened yet._ "

Put the way he's written described it, "a curriculum organized around
applications", I don't think it will. You have it right: too many trees, not
enough forest.

Does anyone who has taken the new MIT curriculum have any comments?

~~~
pretoriusB
Sorry, but what "profound revolution" followed SICP?

It was a mighty fine course and text-book. But where's the revolution?

Where are the guys that were taught SICP that went on to do "revolutionary"
things?

And if they do exist, how do they compare to a control group that just learned
with UNIX/C/C++ and the like?

(Downvotes? I thought we're taking compute SCIENCE here. Where's the science
and the proof? If one didn't know any better he would have thought I was
stoned for insulting some holy scripture...)

~~~
Garoof
> Downvotes? I thought we're taking compute SCIENCE here.

From 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.'

(Don't know about the downvotes or anything. Just thought that was like
vaguely funny.)

------
wangg
"In my experience, relatively few students appreciate how much they're
learning in my course while they're in it."

How true! I hated CS61A when I was in it, and I thought nothing was practical
and everything was a trivial example. Sorry Brian! I failed to grasp the depth
of all the 'trivial' examples. I never appreciated the complexities of the
class until I started being a TA for it, and I never truly loved the class
until I lectured it.

Notes, homeworks, etc, available here: <http://www-
inst.eecs.berkeley.edu/~cs61a/su10/>

------
fomojola
Awesome point about just how language agnostic the course was: the key idea
that every programming language has 3 components (primitives, one or more
means of combination and one or more means of abstraction) and once you figure
those out you can do the same things in just about any other language is
really not highlighted enough. Still haven't seen any other programming
courses that point that out: getting bogged down in syntax trivia seems to be
the pattern of the day.

------
bazzargh
"Courses that teach those languages spend at least half their time just on
learning the notation."

Spot on. This describes exactly my experience of my Pascal-based course back
in 1986 - and it was way more than half. I didn't come across SICP until 10
years later, and it was a revelation, I didn't realise how much more
productive an introductory course could be.

------
lukegru
I was turned onto the SICP lectures[1] though people talking about them on HN,
and I was just floored by them. They still give me goosebumps when I watch
them. It's like watching a video of someone completely in their element and at
the top of their game, like the lecture equivalent of the 2007 Wimbledon
Finals or something.

And of course, the book is awesome too. And it rewards repeat readings.

[1] [http://ocw.mit.edu/courses/electrical-engineering-and-
comput...](http://ocw.mit.edu/courses/electrical-engineering-and-computer-
science/6-001-structure-and-interpretation-of-computer-programs-
spring-2005/video-lectures/)

------
jrajav
Gist.io: <http://gist.io/4076068>

Edit: Uh, why downvote? Not complaining, just curious; I have done this before
for plaintext articles and will do it again, but only if it's welcome.

~~~
andyjohnson0
I don't personally feel strongly about this, but why bother taking a plain
text article written by someone else and re-publishing it in plain text
somewhere else? It doesn't add any value, and just adds noise to the
discussion here. Also, the original author may not appreciate your
republishing their work.

------
stiff
If you are already well versed in SICP you might be interested in the advanced
follow-up class to SICP from Prof. Gerald Sussman:

<http://groups.csail.mit.edu/mac/users/gjs/6.945/>

------
ww520
SICP has wonderful materials to touch on so many important and elegant
concepts in CS that it should be taught to any serious CS students. It's not
about the language Scheme itself but all the underlying CS ideas. You might be
able to learn those concepts here and there from time to time. SICP ties them
in one comprehensive course.

My experience with SICP is a case of after the fact. I've learned and wrote
LISP codes long before touching SICP. The learning process was reading
existing source codes and going through reference materials. It's not until I
went through SICP that suddenly all these concepts and ideas became so clear.

------
rohern
Brian Harvey was a wonderful, wonderful teacher. Most of what I have learned
in CS since has been more-or-less an addendum to his version of CS61A. The
world just doesn't make hackers (and teachers) like that enough.

------
createuniverses
I can't help feeling that this attempt to render a previously excellent course
more commercially viable by making it more superficially appealing for
students is directly linked to this story:
<http://news.ycombinator.com/item?id=4785246>

If everything is always forced to justify itself commercially, then everything
will implode into a hideous, hollow caricature of itself. Everything becomes a
flashy excercise in deceit and con artistry if it wants to survive. Quality
and substance can never hope to win against marketing.

------
spartango
My high-school CS teacher structured his course around SICP--he worked with
Brian Harvey to build the curriculum--and looking back I can definitely see
the power of this approach.

I agree whole-heartedly with what he's said in this piece and hope that others
can continue to reap the value of SICP. It's made me a clearer thinker and
better programmer.

One might say that SICP is unique in as much as it transcends coding as an act
of "slinging code at a screen", pushing readers to think carefully about the
nature and design of their programs. That's only a sliver of what it does, but
it's ever so easy to miss that as a beginning programmer.

Yeah, it definitely takes discipline to get through, but it's quite rewarding.

------
sanxiyn
Is this still true?

"The language in which you'll spend most of your working life hasn't been
invented yet, so we can't teach it to you. Instead we have to give you the
skills you need to learn new languages as they appear."

~~~
shasta
God I hope so.

------
agumonkey
While on the coursera online scala irc chan we discussed other material, SICP
came with sentences like 'rumors made me read it'. This book lives by itself.

------
rustc
As someone who hasn't been able to get enough motivation to read past the
first few pages of SICP, I _really_ wish someone made a TryRuby.org like thing
using SICP.

Please!

~~~
qu4z-2
You mean to give you a scheme REPL?

Because I'm skeptical of the use of transforming SICP into a "tutorial" style.
It's the kind of book that you need to read and think about.

Having said that, finding a REPL that's compatible with it can take a little
bit of time. Personally I quite like GambitC which I seem to recall is fairly
compatible.

------
amirreza
i start reading SICP a week ago, and let me tell you, its like i am actually
re-learning programming with this book! SICP is amazing.

~~~
Derbasti
Watch the video lectures, too. I actually liked them better than the book.

------
ramkalari
The best cs book by a mile. One can't help but fall in love with programming
after reading SICP. I'm now reading Peter Norvig's Paradigms of AI
Programming. It's another classic. I've also listened to video lectures of
Brian Harvey. I think his own twists to SICP such as starting the course with
functions on words instead of numbers are invaluable too.

------
dschiptsov
I just finished watching MIT 6.00SC for the hell of it. It was really sad
experience.

Of course, prof. Guttag is really a big-shot and seems like no one could say
anything, but I cannot even properly describe how much worse it was than CS61A
by Brian Harvey.

It is not just Python, it is ugly Python, boring Python, without any hint of
elegance it could be. No list-set-dict comprehensions, which is what makes
Python interesting, very few slicing examples and one or two use of yield.

I must say that usage of classes was reasonable - only when there were even a
small advantage to structure the code this way, but it is just boring stuff.

Each lecture of CS61 keeps you alert and awake, and curious, time passes
unnoticed, and you almost feel how a new connections growing in your brain,)
while in 6.00CS you're forcing yourself to to stay alert, almost yawning.

So, if one is engaged in self-education just do CS61A and _old_ 6.001 classic
videos. After you can skim trough all those mainstream Python-based courses
very quickly with great ease. I can do 4-5 lectures per day.)

~~~
lesterbuck
Where might I find the CS61A videos? A cursory search found the Brian Harvey
course page at

<http://inst.eecs.berkeley.edu/~cs61a/sp11/>

but the lecture webcasts link seems to be broken

[http://webcast.berkeley.edu/course_details_new.php?seriesid=...](http://webcast.berkeley.edu/course_details_new.php?seriesid=2011-B-26281&semesterid=2011-B)

~~~
ConstantineXVI
I believe you're looking for <http://inst.eecs.berkeley.edu/~cs61AS/fa12/>

~~~
lesterbuck
Thanks! From his note about Scheme not surviving his retirement, I thought he
was gone.

------
Roybatty
We need to start discussing about OO in general. We have a generation (or
two,three in internet time) that think that OO is the epitomy of software
engineering. We have Haskell, Ocaml, and others that can do better

~~~
Evbn
Why haven't they? Success in practice is hard to argue with. Theory can always
sit in the corner, winning every debate by staying above the fray of the dirty
real world, and never get much of anything done.

Please don't attempt to rebut with Real World Haskell, unless you have read
the book and gone on to build a widely deployed application.

------
Roybatty
am i wrong in thinking in the Common Lisp thinking that data and methods don't
belong together? In production environments we at least have extensions
methods in c#, but man i still love generic functions in CL style. Why am i
wrong?

