Ida H. Stamhuis

Hugo de Vries on Heredity, 1889-1903: Statistics, Mendelian Laws, Pangenes, Mutations

The essay describes the development of Hugo de Vriess thinking on heredity from the publication of his Intracellulare Pangenesis in 1889 to the publication of Die Mutationstheorie, Volume 2, in 1903. De Vriess work in the 1890s can be characterized as an attempt to defend his theory of pangenes, especially the fundamental and controversial idea that different characters have different material hereditary carriers. Hybridization experiments served his goal. Recently discovered research notes on hybridization from 1896 suggest that, though he was unaware of Mendels work, De Vries used the laws of dominance and recessiveness, segregation, and independent assortment to explain the 75:25 ratio in the second generation. He had discovered these laws by applying insights from probability theory to his research. In Die Mutationstheorie De Vries combined central concepts of intracellular pangenesis and his mutation theory by modifying the meanings of important terms and introducing new states of pangenes. In his attempts to describe Mendelian crossings in terms of pangenes and mutations, he became entangled in a number of contradictions. Some of his remarks suggest that he was aware that the Mendelian laws and his own theories of pangenes and mutations could not be made consistent.

The Reactions on Hugo de Vries's Intracellular Pangenesis; the Discussion with August Weismann

In 1889 Hugo de Vries published Intracellular Pangenesis in which heformulated his ideas on heredity. The highexpectations of the impression these ideaswould make did not come true and publicationwas negated or reviewed critically. From thereactions of his Dutch colleagues and thediscussion with the famous German zoologistAugust Weismann we conclude that the assertionthat each cell contains all hereditary materialwas controversial and even more the claim thatcharacters are inherited independently of eachother. De Vries felt that he had to convincehis colleagues of the validity of his theory byproviding experimental evidence. He establishedan important research program which resulted inthe rediscovery of Mendels laws and thepublication of The Mutation Theory.This article also illustrates somephenomena that go beyond an interesting episodein the development of theories of heredity. Itshows that criticism from colleagues can move aresearcher so deeply that he feels compelled toset up an extensive research program. Moreoverit illustrates that it is not unusual that acreative scientist is only partially willing totake criticism on his theories into account.Last but not least it demonstrates that commonopinion on the validity of specific argumentsmay change in the course of time.

Adriaan Kluit's statistics and the future of the Dutch state from a European perspective

This article discusses the early history of academic statistics in the Netherlands in relation to the reform challenges of the Dutch state. Statistics, before it developed into a predominantly quantitative social science, was adopted around 1800 by Adriaan Kluit as a method for shaping and articulating his political vision. Kluits politics, the article suggests, echoed the specific outlook on the ‘intrinsic power’ of the Dutch Republic as a trading state that was developed during William IVs stadholderate in the mid eighteenth century. Through the ideas of later writers and statesmen who had trained as statisticians this same approach to envisaging the Dutch future in international trade and politics was carried over into nineteenth-century Dutch political economy and constitutional reform.

The mathematician Rehuel Lobatto advocates life insurances in the Netherlands in the period 1830-1860.

In 1807 the first life insurance society was established in The Netherlands. In the second half of the century, life insurance societies underwent considerable expansion. During the intervening period, the lines had to be laid along which this new phenomenon was to develop in the future: Between 1827 and 1830, the government started discussing the nature of its responsibility in this field and the kind of policy to be developed, and in 1830, a book on the organization of life insurance societies, the calculation of life annuities and widows’ fund premiums was published, written by the mathematician Rehuel Lobatto. This book played an important role in the government’s discussion. Royal Decrees which prescribed government approval for the establishment of life assurance societies were promulgated in 1830, 1833 and 1840. In 1832, Lobatto became the government’s scientific adviser on the assessment of the calculations performed by these societies, and in the same year, he was also appointed adviser to the first life insurance society. From 1832 until his death in 1866 he advised the company on the use of life tables for life as well as for reversionary annuities, and he calculated the premiums based on these life tables. Another decree was promulgated in 1864 prescribing exactly which life tables were to be used. Because Lobatto probably played a part in this decree, he was responsible for a very ‘conservative’ government policy, which was no longer adequate in the second half of the century.