The Varieties of Computation: A Reply

Abstract

I am grateful to the twelve commentators on my article “A Computational Foundation for the Study of Cognition”. The commentaries reflect a great deal of thought by authors many of whom have thought about this topic in more depth than I have in recent years. In many cases, they raise issues that I did not anticipate when I wrote the article and that require me to rethink various aspects of the account I gave there.1 Publication of this symposium, almost twenty years after writing the paper, has encouraged me to dig into my records to determine the article’s history. The roots of the article lie in a lengthy e-mail discussion on the topic of “What is Computation?”, organized by Stevan Harnad in 1992. I was a graduate student in Doug Hofstadter’s AI laboratory at Indiana University at that point and vigorously advocated what I took to be a computationalist position against skeptics. Harnad suggested that the various participants in that discussion write up “position papers” to be considered for publication in the journal Minds and Machines. I wrote a first draft of the article in December 1992 and revised it after reviewer comments in March 1993. I decided to send a much shorter article on implementation to Minds and Machines and to submit a further revised version of the full article to Behavioral and Brain Sciences in April 1994. I received encouraging reports from BBS later that year, but for some reason (perhaps because I was finishing a book and then moving from St. Louis to Santa Cruz) I never revised or resubmitted the article. It was the early days of the web, and perhaps I had the idea that web publication was almost as good as journal publication. Over the years, the article has been discussed here and there, and as it turns out it has been cited about as much as the shorter published article. I have always viewed this article as the more important of the two, and it is good to have it finally published. Over the last two decades the discussion of computation has continued apace and has become much more sophisticated, but as 1This article was published in Journal of Cognitive Science 13: 211-48, 2012. The papers I am replying to are available at http://j-cs.org (issues 12:4, 13:1, 13:2). I would like to thank Gualtiero Piccinini for conceiving and organizing the symposium and also for his comments on a draft of this reply.