View source for Hal Abelson

{{short description|American mathematician}}
{{Use mdy dates|date=October 2024}}
{{Infobox scientist
| honorific_prefix  = 
| name              = Hal Abelson
| honorific_suffix  = 
| image             = HalAbelsonJI1.jpg
| caption           = Abelson in 2007
| birth_date        = {{birth date and age|1947|4|26}}<ref name=loc>{{cite LCAuth|id=n80132755}}</ref>
| birth_place       = 
| birth_name        = Harold Abelson
| death_date        = 
| death_place       = 
| residence         = 
| field             = [[Computer science education]]<br>[[Amorphous computing]]
| work_institutions = [[Massachusetts Institute of Technology]]
| alma_mater        = {{Plainlist |
* [[Princeton University]] ([[Bachelor of Arts|BA]])
* [[Massachusetts Institute of Technology]] ([[PhD]])}}
| doctoral_advisor  = [[Dennis Sullivan]]<ref name=mathgene/>
| doctoral_students = {{plainlist|
*[[Elizabeth Bradley (mathematician and rower)|Elizabeth Bradley]]<ref name=mathgene/>
*[[Mitchel Resnick]]<ref name=mathgene/>
*[[Latanya Sweeney]]<ref name=mathgene/>}}
| thesis_title      = Topologically Distinct Conjugate-Varieties with Finite Fundamental-Group
| thesis_year       = 1973
| thesis_url        = https://mit.primo.exlibrisgroup.com/permalink/01MIT_INST/ejdckj/alma990006784080106761
| known_for         = {{Plainlist|
* [[Creative Commons]]
* [[Public Knowledge]]
* [[Free Software Foundation]]
* [[OpenCourseWare]]<ref name=ocw/>
* ''[[Structure and Interpretation of Computer Programs]]'' (SICP)<ref name=sicp/>}}
| awards            = {{Plainlist|
<!--only include awards notable enough to have dedicated Wikipedia pages-->
* [[SIGCSE Award for Outstanding Contribution to Computer Science Education]] (2012)}}
| website           = {{Official URL}}
| footnotes         = 
}}
'''Harold Abelson''' (born April 26, 1947)<ref name=loc/> is an American mathematician and computer scientist. He is a professor of computer science and engineering in the Department of Electrical Engineering and Computer Science at the [[Massachusetts Institute of Technology]] (MIT), a founding director of both [[Creative Commons]]<ref>{{cite web |url=https://creativecommons.org/about/history |title=Creative Commons: History |access-date=2011-10-09 |archive-url=https://web.archive.org/web/20111007165253/http://creativecommons.org/about/history |archive-date=2011-10-07 |url-status=dead }}</ref> and the [[Free Software Foundation]],<ref name=off/> creator of the [[MIT App Inventor]] platform, and co-author of the widely-used textbook ''[[Structure and Interpretation of Computer Programs]]'' (SICP), sometimes also referred to as "the wizard book" because of its cover illustration.

He directed the first implementation of the language [[Logo (programming language)|Logo]] for the [[Apple II]], which made the language widely available on [[personal computer]]s starting in 1981; and published a widely selling book on Logo in 1982. Together with [[Gerald Jay Sussman]], Abelson developed MIT's introductory computer science subject, "The Structure and Interpretation of Computer Programs" (often referred to by the MIT course number, 6.001), a subject organized around the idea that a computer language is primarily a formal medium for expressing ideas about methodology, rather than just a way to get a computer to perform operations.

Abelson and Sussman also cooperate in codirecting the MIT Project on Mathematics and Computation. The [[MIT OpenCourseWare]] (OCW) project was spearheaded by Abelson and other MIT faculty.<ref name=ocw>{{cite journal|journal=Journal of Science Education and Technology|title=The Creation of OpenCourseWare at MIT|first=Hal |last=Abelson |volume=17|pages=164–174|year=2008|issue=2 |doi=10.1007/s10956-007-9060-8 |bibcode=2008JSEdT..17..164A |hdl=1721.1/37585|s2cid=110449905|hdl-access=free}}</ref>

Abelson led an internal investigation of MIT's choices and role in the prosecution of [[Aaron Swartz]] by the [[Federal Bureau of Investigation]] (FBI), which concluded that MIT did nothing wrong legally, but recommended that MIT consider changing some of its internal policies.

==Education==
Abelson graduated with a [[Bachelor of Arts]] degree in mathematics from [[Princeton University]] in 1969 after completing a senior thesis on ''Actions with fixed-point set: a homology sphere'', supervised by [[William Browder (mathematician)|William Browder]].<ref name=mathgene>{{MathGenealogy}}</ref><ref>{{Cite book|last=Abelson|first=Harold|url=https://catalog.princeton.edu/catalog/3706758|title=Actions with fixed-point set : a homology sphere|date=1969|publisher=Princeton, NJ: Department of Mathematics|language=en}}</ref>

He received his [[PhD]] in mathematics from the [[Massachusetts Institute of Technology]] in 1973 after completing his research on ''Topologically distinct conjugate varieties with finite fundamental group'' supervised by [[Dennis Sullivan]].<ref name="self" /><ref>{{Cite thesis|first=Harold|last=Abelson|year=1973|degree=PhD|publisher=MIT|oclc=30082612|url=https://mit.primo.exlibrisgroup.com/permalink/01MIT_INST/ejdckj/alma990006784080106761|website=mit.edu|access-date=2020-05-31|title=Topologically distinct conjugate varieties with finite fundamental group}}</ref>

==Career and research==
Abelson is also a founding director of [[Creative Commons]] and [[Public Knowledge]], and a director of the [[Center for Democracy and Technology]].<ref>[http://web.mit.edu/echemi/www/030507.html Hal Abelson Playlist] {{Webarchive|url=https://web.archive.org/web/20190314172705/http://web.mit.edu/echemi/www/030507.html |date=2019-03-14 }} Appearance on WMBR's ''[http://web.mit.edu/echemi/www/index.html Dinnertime Sampler] {{Webarchive|url=https://web.archive.org/web/20110504000207/http://web.mit.edu/echemi/www/index.html |date=2011-05-04 }}'' radio show May 7, 2003</ref><ref>{{YouTube|fqtlQWmRvvk|Abelson on Computer Science Education}}</ref><ref>[http://research.google.com/university/relations/visiting-faculty/professor-hal-abelson.html Q&A with Professor Hal Abelson of MIT] on Research at Google</ref><ref name="self">{{cite web |url=http://groups.csail.mit.edu/mac/users/hal/bio.html |title=Hal Abelson |last=Abelson |first=Hal |date=September 17, 2015 |website=Computer Science & Artificial Intelligence Laboratory |publisher=Massachusetts Institute of Technology |access-date=7 September 2019}}</ref>

===Computer science education===
Abelson has a longstanding interest in using computation as a conceptual framework in teaching. He directed the first implementation of [[Logo (programming language)|Logo]] for the [[Apple II]], which made the language widely available on personal computers starting in 1981; and published a widely selling book on Logo in 1982. His book ''[[Turtle Geometry]],'' written with [[Andrea diSessa]] in 1981, presented a computational approach to geometry which has been cited as "the first step in a revolutionary change in the entire teaching/learning process." In March 2015, a copy of Abelson's 1969 implementation of [[Turtle graphics]] was sold at [[The Algorithm Auction]], the world’s first auction of computer [[algorithm]]s.<ref>{{cite web |url=https://www.artsy.net/artwork/hal-abelson-turtle-geometry |title=Hal Abelson – Turtle Geometry |date=1969 |website=Artsy |access-date=7 September 2019}}</ref>

Together with [[Gerald Jay Sussman]], Abelson developed MIT's introductory computer science subject, ''[[Structure and Interpretation of Computer Programs]],'' a subject organized around the notion that a computer language is primarily a formal medium for expressing ideas about methodology, rather than just a way to get a computer to perform operations. This work, through the textbook of the same name, videotapes of their lectures, and the availability on personal computers of the [[Scheme (programming language)|Scheme]] dialect of [[Lisp (programming language)|Lisp]] (used in teaching the course), has had a worldwide impact on university computer science education.<ref>{{cite web|url=http://www.cs.berkeley.edu/~bh/sicp.html |title=Why Structure and Interpretation of Computer Programs matters |last=Harvey |first=Brian |work=Cs.berkeley.edu |date=2011 |access-date=2013-10-06}}</ref><ref name=AwardACM2011/>

He is a visiting faculty member at Google, where he was part of the ''[[App Inventor for Android]]'' team, an educational program aiming to make it easy for people with no programming background to write mobile phone applications and "explore whether this could change the nature of introductory computing".<ref>{{cite web |last=Abelson |first=Hal |title=App Inventor for Android |work=Official Google Research Blog |date=July 31, 2009 |url=https://googleresearch.blogspot.com/2009/07/app-inventor-for-android.html |access-date=August 7, 2009}}</ref> He is coauthor of the book ''App Inventor'' with David Wolber, [[Ellen Spertus]], and Liz Looney, published by O'Reilly Media in 2011.<ref>{{Cite book|url=https://archive.org/details/isbn_9781449397487|url-access=registration|title=App Inventor|last1=Wolber|first1=David|last2=Abelson|first2=Hal|last3=Spertus|first3=Ellen|last4=Looney|first4=Liz|date=2011-05-03|publisher=O'Reilly Media |isbn=9781449308650 |language=en}}</ref><ref>{{Cite news |url=https://www.oreilly.com/library/view/app-inventor-2/9781491907214/ |title=App Inventor 2, 2nd Edition |work=O’Reilly: Safari |access-date=2018-10-25 |language=en}}</ref><ref name="AppInvent">{{cite web |title=App Inventor 2: Create your own Android Apps |url=http://www.appinventor.org/book2 |website=AppInventor.org |access-date=29 June 2019}}</ref> After Google released App Inventor as open source software in late 2009 and provided seed funding to the [[MIT Media Lab]] in 2011, Abelson became codirector of the MIT Center for Mobile Learning to continue development of App Inventor.<ref>{{cite news |title=MIT Launches New Center for Mobile Learning |url=http://web.mit.edu/press/2011/mit-launches-new-center-for-mobile-learning.html |publisher=MIT News Office |date=16 August 2011 |archive-url=https://web.archive.org/web/20110825002738/http://web.mit.edu/press/2011/mit-launches-new-center-for-mobile-learning.html |archive-date=25 August 2011}}</ref>

===Computing tools===
Abelson and Sussman also cooperate in codirecting the MIT Project on Mathematics and Computation, a project of the [[MIT Computer Science and Artificial Intelligence Laboratory]] (CSAIL), formerly a joint project of the [[MIT Artificial Intelligence Laboratory]] (AI Lab) and [[MIT Laboratory for Computer Science]] (LCS), CSAIL's components. The goal of the project is to create better computational tools for scientists and engineers. But even with powerful numerical computers, exploring complex physical systems still requires substantial human effort and human judgement to prepare simulations and to interpret numerical results.<ref name=off/>

Together with their students, Abelson and Sussman are combining methods from [[numerical computation]], [[symbolic algebra]], and [[Heuristic (computer science)|heuristic]] programming to develop programs that not only perform massive numerical computations, but that also interpret these computations and ''discuss'' the results in qualitative terms. Programs such as these could form the basis for intelligent scientific instruments that monitor physical systems based upon high-level behavioral descriptions. More generally, they could lead to a new generation of computational tools that can autonomously explore complex physical systems, and which will play an important part in the future practice of science and engineering. At the same time, these programs incorporate computational formulations of scientific knowledge that can form the foundations of better ways to teach science and engineering.<ref name=off>{{Official URL}}</ref>

===Free software movement===
Abelson and Sussman have also been a part of the [[free software movement]] (FSM), including serving on the [[board of directors]] of the [[Free Software Foundation]] (FSF).<ref name="fsfboard">{{cite web |url=https://www.fsf.org/about/staff-and-board |title=Staff and Board |author=<!--Unstated, staff writer--> |date=<!--Undated--> |website=[[Free Software Foundation]] |access-date=7 September 2019}}</ref>

Abelson is known to have been involved in publishing [[Andrew Huang (hacker)|Andrew Huang]]'s ''Hacking the Xbox'' and [[Keith Winstein]]'s seven-line [[Perl]] [[DeCSS]] script (named [[qrpff]]), and [[Library Access to Music Project]] (LAMP), MIT's campus-wide music distribution system. The [[MIT OpenCourseWare]] (OCW) project was spearheaded by Hal Abelson and other MIT faculty.<ref name=AwardACM2011/><ref>{{cite book |title=Reclaiming Fair Use: How to Put Balance Back in Copyright |last1=Aufderheide |first1=Patricia |last2=Jaszi |first2=Peter |publisher=University of Chicago Press |year=2011 |isbn=9780226032443 |page=53 |url=https://books.google.com/books?id=VWroer9-si8C&pg=PA53}}</ref>

===Aaron Swartz investigation===
{{main|Aaron Swartz}}
In January 2013, [[open access]] activist [[Aaron Swartz]] died by suicide. He had been arrested near MIT and was facing up to 35 years imprisonment for the alleged crime of downloading ''Journal Storage'' ([[JSTOR]]) articles through MIT's ''open access'' campus network.<ref name="SwartzAaronPR">{{cite web
 |url=https://www.justice.gov/archive/usao/ma/news/2011/July/SwartzAaronPR.html
 |title=Alleged Hacker Charged with Stealing Over Four Million Documents from MIT Network
 |author=<!--Unstated, staff writer-->
 |date=July 19, 2011
 |website=The United States Attorney's Office: District of Massachusetts
 |publisher=US Department of Justice
 |access-date=September 7, 2019
 |url-status=live
 |archive-url=https://web.archive.org/web/20120526080523/http://www.justice.gov/usao/ma/news/2011/July/SwartzAaronPR.html
 |archive-date=May 26, 2012
}}</ref>

In response, MIT appointed professor Hal Abelson to lead an internal investigation of the school's choices and role in the prosecution of [[Aaron Swartz]] by the FBI.<ref>{{cite news |url=http://www.huffingtonpost.com/2013/01/15/aaron-swartz-mit_n_2480627.html |date=January 15, 2013 |access-date=January 16, 2013 |title=Aaron Swartz Case 'Snowballed Out of MIT's Hands,' Source Says |last=Smith |first=Gerry |publisher=Huffington Post}}</ref><ref>{{cite web |url=http://web.mit.edu/newsoffice/2013/letter-on-death-of-aaron-swartz.html |date=January 15, 2013 |access-date=January 16, 2013 |title=President Reif writes to MIT community regarding Aaron Swartz,' Source Says |last=Smith |first=Gerry |publisher=MIT News}}</ref><ref>{{cite news |url=https://www.washingtonpost.com/business/technology/anonymous-hacks-mit-sites-to-post-aaron-swartz-tribute-call-to-arms/2013/01/14/ff6f706c-5e44-11e2-9940-6fc488f3fecd_print.html |date=January 15, 2013 |access-date=January 16, 2013 |title=Anonymous hacks MIT sites to post Aaron Swartz tribute, call to arms' Source Says |last=Smith |first=Gerry |newspaper=The Washington Post}}</ref> The report was delivered on July 26, 2013. It concluded that MIT did nothing wrong legally, but recommended that MIT consider changing some of its internal policies.<ref>{{cite web |url=http://swartz-report.mit.edu/docs/report-to-the-president.pdf |title=Report to the President: MIT and the Prosecution of Aaron Swartz |last=Abelson |first=Hal |website=Massachusetts Institute of Technology |date=July 26, 2013 |access-date=2013-08-02}}</ref>

===Awards and honors===
* Designated as one of MIT's six inaugural MacVicar Faculty Fellows, in 1992, in recognition of his significant and sustained contributions to teaching and undergraduate education<ref name="fsfboard"/>
* 1992 Bose Award, the MIT School of Engineering teaching award<ref name="fsfboard"/>
* 1995 [[Taylor L. Booth Education Award]], given by [[IEEE Computer Society]], cited for his continued contributions to the pedagogy and teaching of introductory computer science<ref>{{cite web |url=http://www.computer.org/portal/web/awards/taylorbooth |title=Taylor L. Booth Education Award |publisher=[[IEEE Computer Society]] |access-date=March 28, 2011 |archive-date=January 10, 2011 |archive-url=https://web.archive.org/web/20110110001509/http://www.computer.org/portal/web/awards/taylorbooth |url-status=dead }}</ref>
* 2011 [[Association for Computing Machinery|ACM]] Karl V. Karlstrom Outstanding Educator Award for "his contribution to computing education, through his innovative advances in curricula designed for students pursuing different kinds of computing expertise, and for his leadership in the movement for open educational resources"<ref name=AwardACM2011>{{cite web |url=http://awards.acm.org/award_winners/abelson_4239273.cfm |title=Hal Abelson – Karl V. Karlstrom Outstanding Educator Award – United States – 2011 |publisher=Association for Computing Machinery |access-date=2013-10-11}}</ref>
* 2012 [[Association for Computing Machinery]] (ACM) [[SIGCSE]] Award for [[Outstanding Contribution to Computer Science Education]]<ref>{{cite web |url=http://sigcse.org/programs/awards/outstanding |title=SIGCSE Award for Outstanding Contribution to Computer Science Education |publisher=[[SIGCSE]] |access-date=June 21, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120717072822/http://www.sigcse.org/programs/awards/outstanding |archive-date=July 17, 2012 }}</ref>

===Publications===
* ''[[Structure and Interpretation of Computer Programs]]''<ref name=sicp>{{cite book |last1=Abelson |first1=Harold |last2=Sussman |first2=Gerald Jay |author2-link=Gerald Jay Sussman |last3=Sussman |first3=Julie |date=1996 |title=Structure and Interpretation of Computer Programs, Second Edition |title-link=Structure and Interpretation of Computer Programs |location=Cambridge, Massachusetts |publisher=MIT Press |isbn=0-262-51087-1}}</ref>
* ''Turtle Geometry: The Computer As a Medium for Exploring Mathematics''<ref name=turtle>{{cite book |last1=Abelson |first1=Harold |last2=diSessa |first2=Andrea |author2-link=Andrea diSessa |date=June 1981 |title=Turtle Geometry: The Computer As a Medium for Exploring Mathematics |url=https://direct.mit.edu/books/oa-monograph/4663/Turtle-GeometryThe-Computer-as-a-Medium-for |location=Cambridge, Massachusetts |publisher=MIT Press |isbn=978-0-262-01063-4}}</ref>
* ''Blown to Bits: Your Life, Liberty, and Happiness After the Digital Explosion''<ref name=bits>{{cite book |last1=Abelson |first1=Harold |last2=Ledeen |first2=Ken |last3=Lewis |first3=Harry R. |author3-link=Harry R. Lewis |date=June 20, 2008 |title=Blown to Bits: Your Life, Liberty, and Happiness After the Digital Explosion |location=Saddle River, New Jersey |publisher=Addison-Wesley |isbn=978-0-13-713559-2}}</ref><ref>{{cite web|title=Blown to Bits: Your Life, Liberty, and Happiness After the Digital Explosion|url=http://www.bitsbook.com/|website=Blown to Bits|access-date=29 June 2019}}</ref>
* ''App Inventor 2: Create Your Own Android Apps''<ref name=apppin>{{cite book |last1=Wolber |first1=David |last2=Abelson |first2=Harold |last3=Spertus |first3=Ellen |author3-link=Ellen Spertus |last4=Looney |first4=Liz |date=2014 |title=App Inventor 2: Create Your Own Android Apps 2nd Edition |publisher=O'Reilly Media |isbn=978-1491906842}}</ref><ref name="AppInvent" />

==References==
{{Reflist}}

{{Commons category}}
{{Wikiquote}}

{{Logo programming}}
{{Lisp programming language}}
{{Authority control}}

{{DEFAULTSORT:Abelson, Hal}}
[[Category:American computer scientists]]
[[Category:American artificial intelligence researchers]]
[[Category:Lisp (programming language) people]]
[[Category:Programming language designers]]
[[Category:20th-century American Jews]]
[[Category:20th-century American mathematicians]]
[[Category:21st-century American Jews]]
[[Category:21st-century American mathematicians]]
[[Category:Jewish American scientists]]
[[Category:American electrical engineers]]
[[Category:Princeton University alumni]]
[[Category:Massachusetts Institute of Technology School of Science alumni]]
[[Category:MIT School of Engineering faculty]]
[[Category:Members of the Free Software Foundation board of directors]]
[[Category:Fellows of the IEEE]]
[[Category:Free software programmers]]
[[Category:GNU people]]
[[Category:Living people]]
[[Category:Members of the Creative Commons board of directors]]
[[Category:Google employees]]
[[Category:1947 births]]
[[Category:American computer science educators]]
[[Category:Creative Commons-licensed authors]]
[[Category:Place of birth missing (living people)]]