xx Contents. 



5,6. This cannot be proved directly by statistics ; 



7, 8. Which in certain cases shoiv actual asymmetry. 



9, 10. Nor deductively ; 



11. Nor by the Method of Least Squares. 



12. Distinction between Laws of Error and the Method of Least 



Squares. 



13. Supposed existence of types. 



14 16. Homogeneous and heterogeneous classes. 



17, 18. The type in the case of human stature, &c. 



19, 20. The type in mental characteristics. 



21, 22. Applications of the foregoing principles and results. 



CHAPTER III. 



ORIGIN OR PROCESS OF CAUSATION OF THE SERIES. 



I 1. The causes consist of (1) objects, 



2, 3. Which may or may not be distinguishable into natural kinds. 



46. And (2) agencies. 



7. Requisites demanded in the above : 



8, 9. Consequences of their absence. 



10. Where are the required causes found ? 



11, 12. Not in the direct results of human will. 

 13_15. Examination of apparent exceptions. 

 16 is. Further analysis of some natural causes. 



CHAPTER IV. 



HOW TO DISCOVER AND PROVE THE SERIES. 



1. The data of Probability are established by experience ; 



/ 2. Though in practice most problems are solved deductively. 



3 7. Mechanical instance to show the inadequacy of any a priori proof. 



8. The Principle of Sufficient Reason inapplicable. 



