Lisp is a programmable programming language.
John Foderaro, CACM, September 1991
Lisp is worth learning for the profound enlightenment experience you will have when you finally get it; that experience will make you a better programmer for the rest of your days, even if you never actually use Lisp itself a lot.
Eric Raymond, "How to Become a Hacker"
Lisp has jokingly been called "the most intelligent way to misuse a computer". I think that description is a great compliment because it transmits the full flavor of liberation: it has assisted a number of our most gifted fellow humans in thinking previously impossible thoughts.
Edsger Dijkstra, CACM, 15:10
I object to doing things that computers can do.
Olin Shivers
I used to like arguing over the Internet about this subject. There are many good technical and management/organizational arguments you can make for and against macros. What I've come to realize is they're all pretty much irrelevant.
The entire point of programming is automation. The question that immediately comes to mind after you learn this fact is - why not program a computer to program itself? Macros are a simple mechanism for generating code, in other words, automating programming. Unless your system includes a better mechanism for automating programming (so far, I have not seen any such mechanisms), _not_ having macros means that you basically don't understand _why_ you are writing code.
This is why it is not surprising that most software sucks - a lot of programmers only have a very shallow understanding of why they are programming. Even many hackers just hack because it's fun. So is masturbation.
This is also the reason why functional programming languages ignore macros. The people behind them are not interested in programming automation. Wadler created ML to help automate proofs. The Haskell gang is primarily interested in advancing applied type theory.
Which brings me to my last point: as you probably know, the reputation of the functional programming people as intelligent is not baseless. You don't need macros if you know what you are doing (your domain), and your system is already targeted at your domain. Adding macros to ML will have no impact on its usefulness for building theorem provers. You can't make APL or Matlab better languages for working with arrays by adding macros. But as soon as you need to express new domain concepts in a language that does not natively support them, macros become essential to maintaining good, concise code. This IMO is the largest missing piece in most projects based around domain-driven design.
Will write code that writes code that writes code that writes code for money.
on comp.lang.lisp
Lisp is a language for doing what you've been told is impossible.
Kent Pitman
Anyone could learn Lisp in one day, except that if they already knew Fortran, it would take three days.
Marvin Minsky
Lisp is the red pill.
The greatest single programming language ever designed.
Alan Kay, on Lisp
Within a couple weeks of learning Lisp I found programming in any other language unbearably constraining.
Paul Graham
Greenspun's Tenth Rule of Programming: any sufficiently complicated C or Fortran program contains an ad hoc informally-specified bug-ridden slow implementation of half of Common Lisp.
Philip Greenspun
Historically, languages designed for other people to use have been bad: Cobol, PL/I, Pascal, Ada, C++. The good languages have been those that were designed for their own creators: C, Perl, Smalltalk, Lisp.
Paul Graham
Programming in Lisp is like playing with the primordial forces of the universe. It feels like lightning between your fingertips. No other language even feels close.
Glenn Ehrlich
Lisp doesn't look any deader than usual to me.
David Thornley, reply to a question older than most programming languages
The language God would have used to implement the Universe.
Svein Ove Aas
One of the most important and fascinating of all computer languages is Lisp (standing for "List Processing"), which was invented by John McCarthy around the time Algol was invented.
Douglas Hofstadter, in Gödel, Escher, Bach
Lisp is the most sophisticated programming language I know. It is literally decades ahead of the competition ... it is not possible (as far as I know) to actually use Lisp seriously before reaching the point of no return.
Christian Lynbech
We were not out to win over the Lisp programmers; we were after the C++ programmers. We managed to drag a lot of them about halfway to Lisp. Aren't you happy?
Guy Steele, Java spec co-author Source
Lisp ... made me aware that software could be close to executable mathematics.
L. Peter Deutsch
SQL, Lisp, and Haskell are the only programming languages that I've seen where one spends more time thinking than typing.
I finally understood that the half page of code on the bottom of page 13 of the Lisp 1.5 manual was Lisp in itself. These were "Maxwell's Equations of Software!"
Lisp has all the visual appeal of oatmeal with fingernail clippings mixed in. (Other than that, it's quite a nice language.)
Pascal is for building pyramids -- imposing, breathtaking, static structures built by armies pushing heavy blocks into place. Lisp is for building organisms -- imposing, breathtaking, dynamic structures built by squads fitting fluctuating myriads of simpler organisms into place.
Alan Perlis, in the foreword of Structure and Interpretation of Computer Programs by Harold Abelson and Gerald Jay Sussman Source
The most powerful programming language is Lisp. If you don't know Lisp (or its variant, Scheme), you don't appreciate what a powerful language is. Once you learn Lisp you will see what is missing in most other languages.
One can even conjecture that Lisp owes its survival specifically to the fact that its programs are lists, which everyone, including me, has regarded as a disadvantage.
John McCarthy, "Early History of Lisp"
By policy, LISP has never really catered to mere mortals. And, of course, mere mortals have never really forgiven LISP for not catering to them.
Some may say Ruby is a bad rip-off of Lisp or Smalltalk, and I admit that. But it is nicer to ordinary people.
Yukihiro Matsumoto
You can use C++ if you want with GNOME, but we don't assume that you're going to write C++. It's to a large extent based on Scheme, which is a dialect of LISP. LISP being the most powerful and cleanest of languages, that's the language that's the GNU project always prefers.
APL is like a beautiful diamond - flawless, beautifully symmetrical. But you can't add anything to it. If you try to glue on another diamond, you don't get a bigger diamond. Lisp is like a ball of mud. Add more and it's still a ball of mud - it still looks like Lisp.
Common Lisp people seem to behave in a way that is akin to the Borg: they study the various new things that people do with interest and then find that it was eminently doable in Common Lisp all along and that they can use these new techniques if they think they need them.
Although my own previous enthusiasm has been for syntactically rich languages like the Algol family, I now see clearly and concretely the force of Minsky's 1970 Turing lecture, in which he argued that Lisp's uniformity of structure and power of self reference gave the programmer capabilities whose content was well worth the sacrifice of visual form.
A Lisp programmer knows the value of everything, but the cost of nothing.
DOLIST is similar to Perl's foreach or Python's for. Java added a similar kind of loop construct with the "enhanced" for loop in Java 1.5, as part of JSR-201. Notice what a difference macros make. A Lisp programmer who notices a common pattern in their code can write a macro to give themselves a source-level abstraction of that pattern. A Java programmer who notices the same pattern has to convince Sun that this particular abstraction is worth adding to the language. Then Sun has to publish a JSR and convene an industry-wide "expert group" to hash everything out. That process--according to Sun--takes an average of 18 months. After that, the compiler writers all have to go upgrade their compilers to support the new feature. And even once the Java programmer's favorite compiler supports the new version of Java, they probably still can't use the new feature until they're allowed to break source compatibility with older versions of Java. So an annoyance that Common Lisp programmers can resolve for themselves within five minutes plagues Java programmers for years.
If programming languages were religions...
Lisp would be Zen Buddhism - There is no syntax, there is no centralization of dogma, there are no deities to worship. The entire universe is there at your reach - if only you are enlightened enough to grasp it. Some say that it's not a language at all; others say that it's the only language that makes sense.
...please don't assume Lisp is only useful for Animation and Graphics, AI, Bioinformatics, B2B and E-Commerce, Data Mining, EDA/Semiconductor applications, Expert Systems, Finance, Intelligent Agents, Knowledge Management, Mechanical CAD, Modeling and Simulation, Natural Language, Optimization, Research, Risk Analysis, Scheduling, Telecom, and Web Authoring just because these are the only things they happened to list.
Kent M. Pitman
Lisp isn't a language, it's a building material.
Alan Kay
LISP stands for: Lots of Insane Stupid Parentheses.
LISP stands for: Lots of Irritating Superfluous Parentheses.
Anonymous
In Lisp, if you want to do aspect-oriented programming, you just do a bunch of macros and you're there. In Java, you have to get Gregor Kiczales to go out and start a new company, taking months and years and try to get that to work. Lisp still has the advantage there, it's just a question of people wanting that.
Peter Norvig
