‘From nature to nature’s God’: Ellis A. Davidson—mid-Victorian educator, moralist, and consummate Designer

In recovering the life and work of Ellis Abraham Davidson (1828–1878), this paper draws attention to a Victorian who expands our understanding of Anglo-Jewry as he does not fit the occupational stereotypes. Unusually, he contributed to education, more specifically to the socially-important but frequently neglected topic of technical education. He taught the “lowly” arts, generally known in the nineteenth century as “arts and manufactures”, or the “useful arts”, or “art and design”. Thus although he did not become an artisan or tradesman himself, through his teaching others acquired the requisite skills to become artisans and tradesmen. Moreover, drawing on his experience teaching practical subjects he lectured to Jewish artisans and advised the Board of Guardians on the best way to support apprentices. Finally, and most importantly, this study of Davidson sheds new light on the relations between science, technology, and Judaism in the mid-Victorian period. Thus the final two sections of this paper will examine his commitment to a form of natural theology that set him against Darwin’s theory of evolution and also informed his only book directed specifically at the Anglo-Jewish community.     

Learned changes in the sensitivity of stimulus representations: Associative and nonassociative mechanisms

Central to associative learning theory is the proposal that the concurrent activation of a pair of event representations will establish or strengthen a link between them. Associative theorists have devoted much energy to establishing what representations are involved in any given learning paradigm and the rules that determine the degree to which the link is strengthened. They have paid less attention to the question of what determines that a representation will be activated, assuming, for the case of classical conditioning, that presentation of an appropriately intense stimulus from an appropriate modality will be enough. But this assumption is unjustified. Ipresent the results of experiments on the effects of stimulus exposure in rats that suggest that mere exposure to a stimulus can influence its perceptual effectiveness—that the ability of a stimulus to activate its representation can be changed by experience. This conclusion is of interest for two reasons. First, it supplies a direct explanation for the phenomenon of perceptual learning—the enhancement of stimulus discriminability produced by some forms of stimulus exposure. Second, it poses a theoretical challenge in that it seems to require the existence of a learning mechanism outside the scope of those envisaged by current formal theories of associative learning. I offer some speculations as to how this mechanism might be incorporated into such theories.