PREFACE ix 



enables me to define several of these conceptions much 

 more accurately than was possible in 1892, and to 

 indicate, if only in vague outline, what a fascinating field 

 is being here transferred from the synoptic to the precise 

 division of science (p. 5 1 3). Many changes have been 

 made in the wording, but few in the substance of the 

 earlier parts of this book. For valuable suggestions in 

 Chapters X. and XL I have to thank Mr, Francis Galton, 

 F.R.S., Professor W. F. R. Weldon, F.R.S., and Mr. G. 

 Udny Yule. 



If I have not paid greater attention to my numerous 

 critics, it is not that I have failed to study them ; it is 

 simply that I have remained — obstinately it may be 

 — convinced that the views expressed are, relatively to 

 our present state of knowledge, substantially correct. 

 Such changes in form as I have made have been chiefly 

 suggested by further experience in the difficulties which 

 await both pupil and teacher. I can only conclude by 

 expressing a hope that if old friends meet the Grammar 

 in its new form, they will not be displeased by either the 

 superficial changes or the more substantial additions. 



KARL PEARSON. 



University College, London, 

 Dece7)iber 1899. 



PREFACE TO THE FIRST EDITION 



There are periods in the growth of science when it is 

 well to turn our attention from its imposing superstructure 

 and to carefully examine its foundations. The present 

 book is primarily intended as a criticism of the funda- 

 mental concepts of modern science, and as such finds 

 its justification in the motto placed upon its title-page. 



