The Pleasure of Finding Things Out Read online

  THE PLEASURE OF

  FINDING THINGS OUT

  Also by Richard P. Feynman

  The Character of Physical Law

  Elementary Particles and the Laws of Physics:

  The 1986 Dirac Memorial Lectures (with Steven Weinberg)

  Feynman Lectures on Computation

  (edited by Anthony J. G. Hey and Robin Allen)

  Feynman Lectures on Gravitation

  (with Fernando B. Morinigo and William G. Wagner; edited by Brian Hatfield)

  The Feynman Lectures on Physics

  (with Robert B. Leighton and Matthew Sands)

  The Meaning of It All: Thoughts of a Citizen-Scientist

  Photo-Hadron Interactions

  Perfectly Reasonable Deviations from the Beaten Track:

  The Letters of Richard P. Feynman

  QED: The Strange Theory of Light and Matter

  Quantum Mechanics and Path Integrals (with A. R. Hibbs)

  Six Easy Pieces:

  Essentials of Physics Explained by Its Most Brilliant Teacher

  Six Not-So-Easy Pieces:

  Einstein’s Relativity, Symmetry, and Space-Time

  Statistical Mechanics: A Set of Lectures

  Surely You’re Joking, Mr. Feynman!

  Adventures of a Curious Character (with Ralph Leighton)

  The Theory of Fundamental Processes

  What Do You Care What Other People Think?

  Further Adventures of a Curious Character

  (with Ralph Leighton)

  THE PLEASURE OF

  FINDING THINGS OUT

  The Best Short Works of

  Richard P. Feynman

  RICHARD P. FEYNMAN

  Edited by

  Jeffrey Robbins

  Foreword by

  Freeman Dyson

  A MEMBER OF THE PERSEUS BOOKS GROUP

  NEW YORK

  Copyright © 1999 by Michelle Feynman and Carl Feynman

  Editor’s introduction, chapter introductions, and footnotes copyright © 1999 by Jeffrey Robbins

  Originally published by Perseus Publishing Published by Basic Books, A Member of the Perseus Books Group

  All rights reserved. Printed in the United States of America. Published simultaneously in Canada. No part of this book may be reproduced in any manner whatsoever without written permission except in the case of brief quotations embodied in critical articles and reviews. For information, address Basic Books, 387 Park Avenue South, New York, NY 10016-8810.

  Acknowledgments for previously published material appears on page 259.

  A CIP record for this book is available from the Library of Congress.

  ISBN-13 978-0-465-02395-0

  ISBN-10 0-465-02395-9

  Set in 11-point Berthold Garamond

  Books published by Basic Books are available at special discounts

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  10 9 8

  CONTENTS

  Foreword by Freeman Dyson

  Editor’s Introduction

  1The Pleasure of Finding Things Out

  2Computing Machines in the Future

  3Los Alamos from Below

  4What Is and What Should Be the Role of Scientific Culture in Modern Society

  5There’s Plenty of Room at the Bottom

  6The Value of Science

  7Richard P. Feynman’s Minority Report to the Space Shuttle Challenger Inquiry

  8What Is Science?

  9The Smartest Man in the World

  10Cargo Cult Science: Some Remarks on Science, Pseudoscience, and Learning How to Not Fool Yourself

  11It’s as Simple as One, Two, Three

  12Richard Feynman Builds a Universe

  13The Relation of Science and Religion

  Acknowledgments

  Index

  FOREWORD:

  THIS SIDE IDOLATRY

  by Freeman Dyson

  “I did love the man this side idolatry as much as any,” wrote Elizabethan dramatist Ben Jonson. “The man” was Jonson’s friend and mentor, William Shakespeare. Jonson and Shakespeare were both successful playwrights. Jonson was learned and scholarly, Shakespeare was slapdash and a genius. There was no jealousy between them. Shakespeare was nine years older, already filling the London stage with masterpieces before Jonson began to write. Shakespeare was, as Jonson said, “honest and of an open and free nature,” and gave his young friend practical help as well as encouragement. The most important help that Shakespeare gave was to act one of the leading roles in Jonson’s first play, “Every Man in His Humour,” when it was performed in 1598. The play was a resounding success and launched Jonson’s professional career. Jonson was then aged 25, Shakespeare 34. After 1598, Jonson continued to write poems and plays, and many of his plays were performed by Shakespeare’s company. Jonson became famous in his own right as a poet and scholar, and at the end of his life he was honored with burial in Westminster Abbey. But he never forgot his debt to his old friend. When Shakespeare died, Jonson wrote a poem, “To the Memory of My Beloved Master, William Shakespeare,” containing the well-known lines:

  “He was not of an age, but for all time.”

  “And though thou hadst small Latin and less Greek,

  From thence to honor thee, I would not seek

  For names, but call forth thundering Aeschylus,

  Euripides and Sophocles, . . .

  To live again, to hear thy buskin tread.”

  “Nature herself was proud of his designs,

  And joyed to wear the dressing of his lines, . . .

  Yet I must not give Nature all: Thy art,

  My gentle Shakespeare, must enjoy a part.

  For though the poet’s matter nature be,

  His art does give the fashion; and, that he

  Who casts to write a living line, must sweat, . . .

  For a good poet’s made, as well as born.”

  What have Jonson and Shakespeare to do with Richard Feynman? Simply this. I can say as Jonson said, “I did love this man this side idolatry as much as any.” Fate gave me the tremendous luck to have Feynman as a mentor. I was the learned and scholarly student who came from England to Cornell University in 1947 and was immediately entranced by the slapdash genius of Feynman. With the arrogance of youth, I decided that I could play Jonson to Feynman’s Shakespeare. I had not expected to meet Shakespeare on American soil, but I had no difficulty in recognizing him when I saw him.

  Before I met Feynman, I had published a number of mathematical papers, full of clever tricks but totally lacking in importance. When I met Feynman, I knew at once that I had entered another world. He was not interested in publishing pretty papers. He was struggling, more intensely than I had ever seen anyone struggle, to understand the workings of nature by rebuilding physics from the bottom up. I was lucky to meet him near the end of his eight-year struggle. The new physics that he had imagined as a student of John Wheeler seven years earlier was finally coalescing into a coherent vision of nature, the vision that he called “the space-time approach.” The vision was in 1947 still unfinished, full of loose ends and inconsistencies, but I saw at once that it had to be right. I seized every opportunity to listen to Feynman talk, to learn to swim in the deluge of his ideas. He loved to talk, and he welcomed me as a listener. So we became friends for life.

  For a year I watched as Feynman perfected his way of desc
ribing nature with pictures and diagrams, until he had tied down the loose ends and removed the inconsistencies. Then he began to calculate numbers, using his diagrams as a guide. With astonishing speed he was able to calculate physical quantities that could be compared directly with experiment. The experiments agreed with his numbers. In the summer of 1948 we could see Jonson’s words coming true: “Nature herself was proud of his designs, and joyed to wear the dressing of his lines.”

  During the same year when I was walking and talking with Feynman, I was also studying the work of the physicists Schwinger and Tomonaga, who were following more conventional paths and arriving at similar results. Schwinger and Tomonaga had independently succeeded, using more laborious and complicated methods, in calculating the same quantities that Feynman could derive directly from his diagrams. Schwinger and Tomonaga did not rebuild physics. They took physics as they found it, and only introduced new mathematical methods to extract numbers from the physics. When it became clear that the results of their calculations agreed with Feynman, I knew that I had been given a unique opportunity to bring the three theories together. I wrote a paper with the title “The Radiation Theories of Tomonaga, Schwinger and Feynman,” explaining why the theories looked different but were fundamentally the same. My paper was published in the Physical Review in 1949, and launched my professional career as decisively as “Every Man in His Humour” launched Jonson’s. I was then, like Jonson, 25 years old. Feynman was 31, three years younger than Shakespeare had been in 1598. I was careful to treat my three protagonists with equal dignity and respect, but I knew in my heart that Feynman was the greatest of the three and that the main purpose of my paper was to make his revolutionary ideas accessible to physicists around the world. Feynman actively encouraged me to publish his ideas, and never once complained that I was stealing his thunder. He was the chief actor in my play.

  One of the treasured possessions that I brought from England to America was “The Essential Shakespeare” by J. Dover Wilson, a short biography of Shakespeare containing most of the quotations from Jonson that I have reproduced here. Wilson’s book is neither a work of fiction nor a work of history, but something in between. It is based on the first-hand testimony of Jonson and others, but Wilson used his imagination together with the scanty historical documents to bring Shakespeare to life. In particular, the earliest evidence that Shakespeare acted in Jonson’s play comes from a document dated 1709, more than a hundred years after the event. We know that Shakespeare was famous as an actor as well as a writer, and I see no reason to doubt the traditional story as Wilson tells it.

  Luckily, the documents that provide evidence of Feynman’s life and thoughts are not so scanty. The present volume is a collection of such documents, giving us the authentic voice of Feynman recorded in his lectures and occasional writings. These documents are informal, addressed to general audiences rather than to his scientific colleagues. In them we see Feynman as he was, always playing with ideas but always serious about the things that mattered to him. The things that mattered were honesty, independence, willingness to admit ignorance. He detested hierarchy and enjoyed the friendship of people in all walks of life. He was, like Shakespeare, an actor with a talent for comedy.

  Besides his transcendent passion for science, Feynman had also a robust appetite for jokes and ordinary human pleasures. A week after I got to know him, I wrote a letter to my parents in England describing him as “half genius and half buffoon.” Between his heroic struggles to understand the laws of nature, he loved to relax with friends, to play his bongo drums, to entertain everybody with tricks and stories. In this too he resembled Shakespeare. Out of Wilson’s book I take the testimony of Jonson:

  “When he hath set himself to writing, he would join night to day; press upon himself without release, not minding it till he fainted: and when he left off, remove himself into all sports and looseness again; that it was almost a despair to draw him to his book: but once got to it, he grew stronger and more earnest by the ease.”

  That was Shakespeare, and that was also the Feynman I knew and loved, this side idolatry.

  Freeman J. Dyson

  Institute for Advanced Study

  Princeton, New Jersey

  EDITOR’S INTRODUCTION

  Recently I was present at a lecture at Harvard University’s venerable Jefferson Lab. The speaker was Dr. Lene Hau of the Rowland Institute, who had just conducted an experiment that was reported not only in the distinguished scientific journal Nature but also on the front page of the New York Times. In the experiment, she (with her research group of students and scientists) passed a laser beam through a new kind of matter called a Bose-Einstein condensate (a weird quantum state in which a bunch of atoms, cooled almost to absolute zero, practically stop moving at all and together act like a single particle), which slowed that light beam to the unbelievably leisurely pace of 38 miles per hour. Now light, which normally travels at the breakneck pace of 186,000 miles per second, or 669,600,000 miles per hour, in a vacuum, does typically slow down whenever it passes through any medium, such as air or glass, but only by a fraction of a percent of its speed in vacuo. But do the arithmetic and you will see that 38 miles per hour divided by 669.6 million miles per hour equals 0.00000006, or six-millionths of a percent, of its speed in vacuo. To put this result in perspective, it is as if Galileo had dropped his cannonballs from the Tower of Pisa and they took two years to reach the ground.

  I was left breathless by the lecture (even Einstein would have been impressed, I think). For the first time in my life I felt a smidgen of what Richard Feynman called “the kick in the discovery,” the sudden feeling (probably akin to an epiphany, albeit in this case a vicarious one) that I had grasped a wonderful new idea, that there was something new in the world; that I was present at a momentous scientific event, no less dramatic or exciting than Newton’s feeling when he realized that the mysterious force that caused that apocryphal apple to land on his head was the same force that caused the moon to orbit the earth; or Feynman’s when he achieved that first grudging step toward understanding the nature of the interaction between light and matter, which led eventually to his Nobel Prize.

  Sitting among that audience, I could almost feel Feynman looking over my shoulder and whispering in my ear, “You see? That’s why scientists persist in their investigations, why we struggle so desperately for every bit of knowledge, stay up nights seeking the answer to a problem, climb the steepest obstacles to the next fragment of understanding, to finally reach that joyous moment of the kick in the discovery, which is part of the pleasure of finding things out.”* Feynman always said that he did physics not for the glory or for awards and prizes but for the fun of it, for the sheer pleasure of finding out how the world works, what makes it tick.

  Feynman’s legacy is his immersion in, and dedication to, science–its logic, its methods, its rejection of dogma, its infinite capacity to doubt. Feynman believed and lived by the credo that science, when used responsibly, can not only be fun but can also be of inestimable value to the future of human society. And like all great scientists, Feynman loved sharing his wonder of nature’s laws with colleagues and lay-persons alike. Nowhere is Feynman’s passion for knowledge more clearly displayed than in this collection of his short works (most previously published, one unpublished).

  The best way to appreciate the Feynman mystique is to read this book, for here you will find a wide range of topics about which Feynman thought deeply and discoursed so charmingly, not only physics–in the teaching of which he was surpassed by no one–but also religion, philosophy, and academic stage fright; the future of computing, and of nanotechnology, of which he was the first pioneer; humility, fun in science, and the future of science and civilization; how budding scientists should view the world; and the tragic bureaucratic blindness that led to the Space Shuttle Challenger disaster, the headline-making report that made “Feynman” a household word.

  Remarkably, there is very little overlap in these pieces, but in thos
e few places where a story is repeated in another piece, I took the liberty of deleting one of the two occurrences to spare the reader needless repetition. I inserted ellipses (. . .) to indicate where a repeated “gem” has been deleted.

  Feynman had a very casual attitude toward proper grammar, as clearly shows in most of the pieces, which were transcribed from spoken lectures or interviews. To maintain the Feynman flavor, therefore, I generally let stand his ungrammatical turns of phrase. However, where poor or sporadic transcription made a word or phrase incomprehensible or awkward, I edited it for readability. I believe that the result is virtually unspoiled, yet readable, Feynmanese.

  Acclaimed during his lifetime, revered in memory, Feynman continues to be a source of wisdom to people from all walks of life. I hope this treasury of his best talks, interviews, and articles will stimulate and entertain generations of devoted fans and newcomers to Feynman’s unique and often rambunctious mind.

  So read, enjoy, and don’t be afraid to laugh out loud occasionally or to learn a lesson or two about life; be inspired; above all, experience the pleasure of finding things out about an uncommon human being.

  I would like to thank Michelle and Carl Feynman for their generosity and constant support from both coasts; Dr. Judith Goodstein, Bonnie Ludt, and Shelley Erwin of the Caltech archives for their indispensable help and hospitality; and especially professor Freeman Dyson for his elegant and enlightening Foreword.

  I would also like to express my thanks to John Gribbin, Tony Hey, Melanie Jackson, and Ralph Leighton for their frequent and excellent advice throughout the making of this book.

  Jeffrey Robbins,

  Reading, Massachusetts,

  September 1999

  *Another of the most exciting events, if not in my life, then at least in my publishing career, was finding the long-buried, never-before-published transcript of three lectures Feynman gave at the University of Washington in the early 1960s, which became the book The Meaning of It All; but that was more the pleasure of finding things than the pleasure of finding things out.