ON THE FUNDAMENTAL CONCEPTIONS OF 
BIOLOGY. 
By KARL PEARSON. 
The contrast between the old and new methods of dealing with biological 
conceptions has been recently emphasised by the publication of my memoir on 
Honiotyposis*, and of Mr W. Bateson's criticism of it entitled, "Heredity, 
Differentiation, and other Conceptions of Biologyf." To the biometrician it is 
a sine qua non that the conceptions upon which the theory of evolution is founded 
shall be concisely defined. Under such conditions only can they be quantitatively 
expressed, and without quantitatively exact expression it is impossible to use 
statistical methods. If the question be raised : Why are statistical methods to be 
used ? the answer is clear: Because the whole problem of evolution is a problem 
in vital statistics — a problem of longevity, of fertility, of health, and of disease, and 
it is as impossible for the evolutionist to proceed without statistics, as it would be 
for the Registrar-General to discuss the national mortality without an enumeration 
of the population, a classification of deaths, and a knowledge of statistical theory. 
Yet this it seems to me is precisely what the school of biologists represented by 
Mr Bateson are attempting to do. I speak advisedly of the " school of biologists," 
for the matter is much wider than an individual controversy between Mr Bateson 
and myself His paper which directly or indirectly attacks all the biometric work 
of the past ten years was published by the Royal Society at the recommendation 
and with the approval of its Zoological Committee. That Committee embraced 
some of the most distinguished English biologists, and we may therefore reasonably 
suppose that they attach meaning and weight to the terms used by Mr Bateson. 
They have made themselves a party to the controversy by allowing the issue 
under their aegis of extremely disputable matter, and matter which I believe can 
* " Mathematical Coutributious to the Theory of Evolution. IX. On the Principle of Homotyposis 
and its relation to Heredity, to the Variability of the Individual and to that of the Eace. Part I. 
Homotyposis in the Vegetable Kingdom." Phil. Trans. Vol. 197, pp. 285—379 (Dulau and Co., Soho 
Square, London). 
t II. S. Proc. Vol. G9, pp. 193—205. 
