The following excerpt is reproduced from
Michael A. Gottlieb’s *Introduction* in *Feynman's Tips on Physics: A
Supplement to the Feynman Lectures on Physics, *by * *Richard P. Feynman, Michael A. Gottlieb and Ralph
Leighton* (*Addison-Wesley, 2005).

I first heard of
Richard Feynman and Ralph Leighton in 1986, through their entertaining book *Surely** You’re Joking, Mr. Feynman! *Thirteen
years later I met Ralph at a party. We became friends, and over the next year
we worked together on the design of a fantasy stamp honoring Feynman. [1] All the while Ralph was giving me books to read, by or
about Feynman, including (since I am a computer programmer) *Feynman Lectures
on Computation. *[2] The discussion of quantum mechanical
computation in this fascinating book intrigued me, but without having studied
quantum mechanics, I had difficulty following the arguments. Ralph recommended
I read *The Feynman* *Lectures on Physics Volume III: Quantum
Mechanics, *which I began, but
Chapters 1 and 2 of *Volume III *are reproduced from Chapters 37 and 38 of *Volume I, *so I found myself backtracking through
references in *Volume I*
rather than progressing through *Volume III. *I therefore decided to read all *The Feynman Lectures *from
beginning to end—I was determined to learn some quantum mechanics!
However, that goal became secondary as time went on and I became increasingly
absorbed in Feynman’s fascinating world. The joy of learning physics, simply
for the pleasure of it, became my highest priority. I was hooked! About halfway
through *Volume I, *I took a break from programming and spent six months
in rural Costa Rica studying *The Lectures *full-time.

Every
afternoon I studied a new lecture and worked on physics problems; in the
mornings I reviewed and proofread yesterday’s lecture. I was in e-mail contact
with Ralph, and he encouraged me to keep track of errors I mentioned
encountering in *Volume I. *It was not much of a burden, because there
were very few errors in that volume. However, as I progressed through *Volumes
II *and *III, *I was dismayed to discover increasingly more errors. In
the end I had compiled a total of more than 170 errors in
in *The
Lectures. *Ralph and I were surprised: how could so many errors
have been overlooked for so long? We decided to see what could be done about
getting them corrected in the next edition.

Then I noticed some intriguing sentences in Feynman’s preface:

"The reason there are no lectures on how to solve problems is because there were recitation sections. Although I did put in three lectures in the first year on how to solve problems, they are not included here. Also there was a lecture on inertial guidance which certainly belongs after the lecture on rotating systems, but which was, unfortunately, omitted."

This suggested the idea of reconstructing the missing
lectures and, if they proved interesting, offering them to Caltech and Addison
Wesley for inclusion in a more complete and error-corrected edition of *The
Lectures. *But first I had to *find *the
missing lectures, and I was still in Costa Rica! Through a bit of deductive
logic and investigation, Ralph was able to locate the lecture notes,
which were previously hidden away somewhere between his father’s office and the
Caltech Archives. Ralph also obtained tape recordings of the missing lectures,
and while researching errata in the Archives after my return to California, I
fortuitously discovered the blackboard photos (long believed lost) in a box of
miscellaneous negatives. The Feynman heirs generously gave us permission to use
these materials, and so, with some useful critiques from Matt Sands, now the
only surviving member of the Feynman-Leighton-Sands trio, Ralph and I
reconstructed *Review B *as a sample, and presented it with the errata for
*The Lectures *to Caltech and Addison Wesley.

Addison Wesley received our ideas enthusiastically,
but Caltech was initially skeptical. Ralph therefore appealed to Kip Thorne,
Richard Feynman Professor of Theoretical Physics at Caltech, who eventually
managed to achieve a mutual understanding among all involved, and who
generously volunteered his time to oversee our work. Since Caltech did not want
to amend the existing volumes of *The Lectures *for historical reasons,
Ralph proposed putting the missing lectures in a separate book. That is the
origin of this supplementary volume. It is being published in parallel with a
new *Definitive Edition *of *The Feynman Lectures on Physics, *in
which the errors I found are corrected, as are other errors found by a number
of other readers.

Mike Gottlieb

Playa Tamarindo, Costa Rica

[1] Our stamp appears in the liner notes of *Back TUVA
Future, *a CD featuring the Tuvan throat-singing master *Ondar *and a cameo
appearance by Richard Feynman (Warner Bros. 9 47131-2), released in 1999.

[2] *Feynman Lectures on Computation, *by Richard P.
Feynman, edited by Anthony J. G. Hey and Robin W. Allen, 1996, Addison-Wesley,
ISBN 0-201-48991-0.