Book description
Originally published in 1931. SCIENTIFIC INFERENCE SCIENTIFIC INFERENCE
by HAROLD JEFFREYS M. A., D. Sc., F R. S. Contents include: Preface
.,....., P a g e vii Chapter I LOGIC AND SCIENTIFIC INFERENCE ... i
Chapter II PROBABILITY 8 Chapter III SAMPLING 24 Chapter IV QUANTITATIVE
LAWS 36 Chapter V ERRORS 52 Chapter VI PHYSICAL MAGNITUDES 84 Chapter
VII MENSURATION 107 Chapter VIII NEWTONIAN DYNAMICS 131 Chapter IX LIGHT
AND RELATIVITY 159 VI CONTENTS Chapter X MISCELLANEOUS QUESTIONS . . .
page 191 Chapter XI OTHER THEORIES OF SCIENTIFIC KNOWLEDGE . 218
Appendix I PROBABILITY IN LOGIC AND PURE MATHEMATICS . 229 Appendix II
INFINITE NUMBERS 232 Appendix III THE ANALYTIC TREATMENT OF THE SINE AND
COSINE 237 Lemmas 240 Index 245: PREFACE: THE present work had its
beginnings in a series of papers published jointly some years ago by Dr
Dorothy Wrinch and myself. Both before and since that time several books
pur porting to give analyses of the principles of scientific inquiry
have appeared, but it seems to me that none of them gives adequate
attention to the chief guiding principle of both scientific and everyday
knowledge that it is possible to learn from experience and to make
inferences from it beyond the data directly known by sensation.
Discussions from the philosophical and logical point of view have tended
to the con clusion that this principle cannot be justified by logic
alone, which is true, and have left it at that. In discussions by
physicists, on the other hand, it hardly seems to be noticed that such a
principle exists. In the present work the principle is frankly adopted
as a primitive postulate and its consequences are developed. It is found
to lead to an explanation and a justification of the high probabilities
attached in practice to simple quantitative laws, and thereby to a
recasting of the processes involved in description. As illustrations of
the actual relations of scientific laws to experience it is shown how
the sciences of mensuration and dynamics may be developed. I have been
stimulated to an interest in the subject myself on account of the fact
that in my work in the subjects of cosmo gony and geophysics it has
habitually been necessary to apply physical laws far beyond their
original range of verification in both time and distance, and the
problems involved in such extrapolation have therefore always been
prominent. My thanks are due to the staff of the Cambridge Univer sity
Press for their care and courtesy also to Dr Wrinch and Mr M. H. A.
Newman, who have read the whole in proof and suggested many
improvements. HAROLD JEFFREYS ST JOHNS COLLEGE CAMBRIDGE January 1931.
CHAPTER I: LOGIC AND SCIENTIFIC INFERENCE Contrariwise, continued
Tweedledee, if it was so, it might be and if it were so, it would be but
as it isnt, it aint. Thats logic. LEWIS CARROLL, Through the Looking
Glass 1-1. The fundamental problem of this work is the question of the
nature of scientific inference. The data available to the scientific
worker, as well as to the man in the street, are com posed of two
classes. The first class consists of the crude data provided by the
senses. These will be called sensations. The second class consists of
general principles, which determine how the information provided by the
senses is to be treated. It is actually treated in two different ways,
which may be called description and inference. Description, in the
strict sense, would involve only the cataloguing and classification of
sensations already experienced. Inference is the use of sen sations
already experienced to derive information about sen sations not yet
experienced, to construct physical objects, and to describe the past and
future of these physical objects. For pure description only an
application of the principles of classification and the properties of
classes is required these are purely logical ideas. Inference requires
much more...
