~ ROA Version, 8/2002. Essentially identical to the Tech Report, with new pagination (but the same
footnote and example numbering); correction of typos, oversights & outright errors; improved typography;
and occasional small-scale clarificatory rewordings. Citation should include reference to this version.
OPTIMALITY THEORY
Constraint Interaction in Generative Grammar
First circulated: April, 1993
RuCCS-TR-2; CU-CS-696-93: July, 1993
Minor Corrections: December, 1993
ROA Version: August, 2002
Alan Prince Paul Smolensky
Department of Linguistics Department of Cognitive Science
Rutgers Cognitive Science Center The Johns Hopkins University
Rutgers University [1993: University of Colorado at Boulder]
prince@ruccs.rutgers.edu smolensky@cogsci.jhu.edu
Everything is possible but not
everything is permitted �
� Richard Howard, �The Victor Vanquished�
�It is demonstrated,� he said, �that things cannot be
otherwise: for, since everything was made for a purpose,
everything is necessarily made for the best purpose.�
� Candide ou l�optimisme. Ch. I.
Remark. The authors� names are arranged in lexicographic order.

Acknowledgments
Special thanks to John McCarthy for detailed discussion of virtually every issue raised here and for
a fine-grained skepsis of the entire first draft of the ms., which resulted in innumerable
improvements and would have resulted in innumerably more, were this a better world. We are
particularly grateful for his comments and suggestions in r‘ Chs. 7 and 9. We also wish to thank
Robert Kirchner, Armin Mester, and Junko It� for remarks that have had significant impact on the
development of this work, as well as David Perlmutter, Vieri Samek-Lodovici, Cheryl Zoll,
Henrietta Hung, Mark Hewitt, Jane Grimshaw, Ad Neeleman, Diana Archangeli, Henry Churchyard,
Doug Pulleyblank, Moira Yip, Tom Bever, Larry Hyman, Andy Black, Mike Jordan, Lauri
Karttunen, Ren� Kager, Paul Kiparsky, Mike Kenstowicz, Ellis Visch, Andr�s Kornai, Akin
Akinlabi, G�raldine Legendre, Clayton Lewis, Merrill Garrett, Jim Martin, Clara Levelt, Mike
Mozer, Maria Bittner, Alison Prince, Dave Rumelhart, Mark Liberman, Jacques Mehler, Steve
Pinker, Daniel B�ring, Katharina Hartmann, Joshua Legendre Smolensky, Ray Jackendoff, Bruce
Hayes, Geoff Pullum, Gyanam Mahajan, Harry van der Hulst, William Labov, Brian McHugh, Gene
Buckley, Will Leben, Jaye Padgett and Loren Billings. None of these individuals can be sensibly
charged with responsibility for any errors that may have crept into this work.
To Merrill Garrett (Cognitive Science, University of Arizona, Tucson) and to the organizers
of the Arizona Phonology Conference we are grateful for providing in April 1991 the first public
forums for the presentation of the theory, which proved a significant stimulus to the cohering thereof.
We would also like to thank audiences at our 1991 LSA Summer Institute course and at the Feature
Workshop there, at WCCFL 1992, at the OTS (Utrecht), University of California at Berkeley
(Phonology Laboratory), the University of Colorado at Boulder and the Boulder Connectionist
Research Group, Rutgers University (New Brunswick and Piscataway), Brandeis University, the
University of Pennsylvania (the Linguistics Department and the Institute for Research in Cognitive
Science), Princeton University Cognitive Science Center, Stanford University (Phonology Workshop
and Parallel Distributed Processing Seminar), the University of Rochester Cognitive Science
Program, and the International Computer Science Institute of Berkeley CA.
Financial support was provided by a University of Colorado Faculty Fellowship, by research
funds from Rutgers University and from the Rutgers Center for Cognitive Science, and, most
crucially, by NSF SGER BNS-90 16806 without which the rigors of long-distance collaboration
would have proved daunting indeed.
We remember Robert Jeffers with special appreciation for constructing the Rutgers
environment that so greatly facilitated the progress of this work.