*Foreword*

Brian Cantwell Smith was born in Montreal, Canada, on 1 December 1949.
Growing up first there and later in Cambridge, Massachusetts, he
remains a Canadian citizen.  Multiple allegiances, sometimes
conflicting but mostly complementary, have characterized both his
personal and intellectual life ever since.

He started undergraduate study at Oberlin College in Ohio in 1967,
where his interests included both physics and religion but left after
only two years, travelling first to visit the Quaker community
Argenta, British Columbia, and ending up in Ottawa where he started
work as a programmer at the Division of Physics laboratory of the
National Research Council of Canada, working on a project jointly
involving Fermilab in Chicago and the Lawrence Research Laboratory in
Berkeley.  Working at all three sites on PDP 9 and PDP 15
microcomputers, he "programmed like crazy" in machine language,
building systems for experimental control and data gathering.
  
When the project ended Brian moved back to the family home in
Cambridge, and started taking classes at the Massachusetts Institute
of Technology (MIT), studying what was then known as Social Inquiry,
in particular the politics of high technology.  But it quickly became
apparent that the understanding of computing that the social
scientists were critiquing was not the computing that he knew as a
programmer, what he later came to refer to as "computing in the wild".

"What drove me out of Social Inquiry and back to [Computer Science] was
needing to be back in the practice.  That skill was not somthing that
people on the outside understood."

Brian had realised that in order to legitimately critique Computer
Science, he needed to get clear on what computing really is: "I had to
go into the heart of the beast, as it were". So he applied for the PhD
program in Electrical Engineering and Computer Science at MIT and
began taking classes there.

When the MIT administration discovered Brian didn't have an
undergraduate degree, and so couldn't be registered for graduate
study, Patrick Winston, the newly-appointed head of the Artificial
Intelligence Laboratory, gave Brian an informal oral exam in topics
from the MIT undergraduate computer science curriculum and awarded him
the credits necessary for a degree, clearing the way for his admission
to the graduate program.

In 1976 Terry Winograd, who had left MIT to join the Computer Science
Lab at the Xerox Palo Alto Research Center (PARC), invited Brian to
spend the summer in the Understander Group there, where he joined in
the development of KRL, a Knowledge Representation Language, which
came to embody some of the ideas that were developed in his Masters
and PhD dissertations [refs].

These biographical details bring us to the brink of Brian's
professional life, and to the time and place where we first met. The
point made above about multiple allegiances can be succinctly
summarized by a list of the positions he has occupied since the
completion of his PhD a few years later:

 * Member of the Scientific Staff, Xerox PARC
 * Director, Xerox PARC System Sciences Lab
 * Adjunct Professor of Philosophy, Stanford University
 * Founding member of Stanford University's Center for the Study of
   Language and Information
 * Founding member and first president, Computer Professionals for
   Social Responsibility
 * President of the Society for Philosophy and Psychology
 * Professor of Cognitive Science, Computer Science, and Philosophy,
   Indiana University
 * Kimberly J. Jenkins University Distinguished Professor of
   Philosophy and New Technologies, Duke University
 * Dean of the Faculty of Information, University of Toronto
 * Invited keynote speaker, _Défaire l'Occident_, Plainartige, France
 * Professor of Information, Philosophy, Cognitive Science, and the
   History and Philosophy of Science and Technology, University of
   Toronto
 * Senior Fellow, Massey College, University of Toronto
 * Reid Hoffman Professor of Artificial Intelligence and the Human,
   University of Toronto

It was during Brian's years in Palo Alto at PARC, at first just for
the summer and then full-time, that the foundations were laid for the
work that led to this book.

  "As an exercise in using KRL representational structures, Brian
   Smith tried to describe the KRL data structures themselves in
   KRL-0. A brief sketch was completed, and in doing it we were made
   much more aware of the ways in which the language was inconsistent
   and irregular. This initial sketch was the basis for much of the
   development in KRL-1."  [ref. Bobrow and Winograd 1978, "Experience
   with KRL-O: One Cycle of a Knowledge Representation Language", in
   _Proceedings of the Fifth International Joint Conference on
   Artificial Intelligence_, Morgan Kaufmann Publishers, Burlington,
   MA.  Available online at
   https://www.ijcai.org/Proceedings/77-1/Papers/032.pdf].

Brian's input into the (never completed) KRL-1 meant that not only
could some parts of a system's data be _about_ other parts, but that
this would be more than just commentary. It would actually play a role
in the system's operation. For KRL-1, this was initially motivated by
a desire to formulate aspects of knowledge representation such as
negation and disjunction as, if you will, knowledge about knowledge,
rather than as primitives built into the vocabulary of the
representation language itself. [elaborate this with reference to
old-style Semantic Nets and Bobrow and Norman ?]

Brian's development of this idea, which he termed 'reflection', is
documented in the papers gathered in _Legacy_.  But its title
notwithstanding, this book is _not_ a recapitulation of that work.

There was an assumption at the heart of Brian's reflective
architectures, which was initially expected to occupy just one section
of one chapter of his PhD, as signalled in its preliminary outline
Table of Contents.  But its resolution proved to be much more
problematic than expected, to the extent that it has taken
a lifetime of work for Brian to bring it clearly into focus.

Looking back it seems that this difficulty acted rather like the grit
in the oyster, stimulating Brian's wholesale reconsideration of the
nature of computation, and Computer Science as currently practiced,
which _is_ what this book is about.

You'll have to read the book to find out what that assumption was, and
the details of the critique of Computer Science that it led Brian to.

It may seem rather presumptuous of me to suggest that this one person
has accurately diagnosed a problem that a whole field of enquiry has
missed, to the point where they've ended up altogether stuck, unable
to see what they've missed.  The point of the list offered above of
Brian's achievements and the manifest breadth of his background it
testifies to will I hope give sufficient grounds for suggesting that
it is at least possible that this indeed just might be worth checking
out.

As Brian himself said about this recently "That this is important
needs to be said.  And it's not about _me_, that is, it's not
important because I say it is."  That it's important to him does
however mean that his claim deserves our attention.

This is not an easy book to read, but it's a very important book, so
it's worth the effort.  As Brian himself has said, it's written rather
like a detective story, in which the same underlying set of facts is
explored repeatedly, getting closer each time to a complete and
self-consistent picture.  When I first read it, I said to Brian more
than once "But you keeping using [some term], and it's clear you mean
it in some important, technical, sense, but you haven't _defined_ it".
And he said, "Look, what I've writen should be read more like novel
than like a manual.  What things mean will gradually take shape.  Be
patient".

If you care about computer science, either as a practioner, or a
theorist, or a concerned citizen, this book matters for you.  It's
conclusions matter, even if parts of it are not meant for you.  So
even if you find it hard, as a computer programmer, to see why you
should care if the theorists have got it wrong, be patient.  If you're
a theorist, and you find Brian's critique at best irrelevant, and at
worst aggresive, obnoxius and founded in misunderstanding, be patient.
If you're a citizen, and the technical details are off-putting, be
patient.

If you _are_ patient, and stay the course, when you get to the end you
will realise that you actually do understand the terminology now, and
that even though the work that remains is hugely challenging, and
perhaps only imperfectly grasped by Brian himself, much less the rest
of us, getting it done matters for all of us.  As practioners and
theorists, we need to ask ourselves what we can do to make Brian's
vision a reality.  As citizens, we need to cheer from the sidelines,
and keep asking questions.  We owe him that much.

Henry S. Thompson, Toronto and Edinburgh, November 2024.

*Epigraph*

   Therefore, I close with the following dramatic but also perfectly
   serious claim: cognitive science and artificial intelligence cannot
   succeed in their own essential aims unless and until they can
   understand and/or implement genuine freedom and the capacity to
   love.

       John Haugeland, "Authentic Intentionality", 2002