A highly technical theory of visual perception is developed in the first half of this psychological study with the aid of set-theoretical symbols and a complex array of variables ranging over states of the various sub-systems of the organism related to perception. In the later chapters the author describes several new and crucial experiments favoring the theory over other theories of perception, and discusses its philosophical implications for a behavioral account of mind. Those who wade through the welter of (...) symbols will find important material for a philosophy of perception in the theory and especially in the experiments, involving externally induced environmental changes which are corrected by the behavior of the organism over a period of time. --R. H. K. (shrink)

Late in 1990, the Center for the Study of Ethics in the Professions at Illinois Institute of Technology (lIT) received a grant of more than $200,000 from the National Science Foundation to try a campus-wide approach to integrating professional ethics into its technical curriculum.! Enough has now been accomplished to draw some tentative conclusions. I am the grant's principal investigator. In this paper, I shall describe what we at lIT did, what we learned, and what others, especially philosophers, can learn (...) from us. We set out to develop an approach that others could profitably adopt. I believe that we succeeded. (shrink)

Introduction: Although deep brain stimulation often improves levodopa-responsive gait symptoms, robust therapies for gait dysfunction from Parkinson's disease remain a major unmet need. Walking speed could represent a simple, integrated tool to assess DBS efficacy but is often not examined systematically or quantitatively during DBS programming. Here we investigate the reliability and functional significance of changes in gait by directional DBS in the subthalamic nucleus.Methods: Nineteen patients underwent unilateral subthalamic nucleus DBS surgery with an eight-contact directional lead in the most (...) severely affected hemisphere. They arrived off dopaminergic medications >12 h preoperatively and for device activation 1 month after surgery. We measured a comfortable walking speed using an instrumented walkway with DBS off and at each of 10 stimulation configurations at the midpoint of the therapeutic window. Repeated measures of ANOVA contrasted preoperative vs. maximum and minimum walking speeds across DBS configurations during device activation. Intraclass correlation coefficients examined walking speed reliability across the four trials within each DBS configuration. We also investigated whether changes in walking speed related to modification of step length vs. cadence with a one-sample t-test.Results: Mean comfortable walking speed improved significantly with DBS on vs. both DBS off and minimum speeds with DBS on. Pairwise comparisons showed no significant difference between DBS off and minimum comfortable walking speed with DBS on. Intraclass correlations were ≥0.949 within each condition. Changes in comfortable walk speed were conferred primarily by changes in step length.Conclusion: Acute assessment of walking speed is a reliable, clinically meaningful measure of gait function during DBS activation. Directional and circular unilateral subthalamic DBS in appropriate configurations elicit acute and clinically significant improvements in gait dysfunction related to PD. Next-generation directional DBS technologies have significant potential to enhance gait by individually tailoring stimulation parameters to optimize efficacy. (shrink)

The Brotherton Collection, which now forms part of the Library of the University of Leeds, contains a manuscript of Cicero's De Officiis which is usually assigned to the twelfth century. On page 3 of the catalogue of the Brotherton Library the manuscript is incorrectly said to contain ‘DE OFFICIIS LIBER PRIMUS’. In fact the manuscript contains all three books with the exception of nine leaves which have been removed. At present the manuscript consists of 41 folios on vellum measuring 11 (...) in. X 7½ in. Ff. 39–41 are written by a later hand. (shrink)

In this paper I contrast two causal explanations of the outcome of a set of laboratory experiments in population ecology conducted by Thomas Park in the 1940s and 1950s. These experiments shed light on the problem of adducing evidence for the operation of competition (see Lloyd 1987 for a recent philosophical discussion) and are central to the group selection controversy because they form the empirical base for experimental studies of group selection conducted over the last 12 years (see Griesemer and (...) Wade 1988 for an analysis).The experiments investigated competition in laboratory populations of two flour beetle species, Tribolium confusum and Tribolium castaneum, but the results were more complex and interesting than expected; in addition to demonstrating competition in a laboratory system, they exhibited what Park called “competitive indeterminacy.” This phenomenon was of great interest to statisticians, who devised stochastic models to describe its demographic basis (e.g., M.S. Bartlett, P.H. Leslie, and J. Neyman; see Mertz 1972 for references). (shrink)

This article sheds new light on late-19th-century debates about the organization of knowledge through its emphasis on German orientalism and comparative linguistics. Centering on Friedrich Carl Andreas’ (1846–1930) controversial reconstruction of the Avestan language and its sacred literary corpus, I highlight a shift from the history of texts to an engagement with ‘living’ language in the decades around 1900. Andreas is shown to have inherited aspects of two schools, which collectively defined the landscape of 19th-century philological research – one traditional (...) and the other comparative. The long-standing struggle between these schools demonstrates that ‘the humanities’ were no monolithic foil to the rise of natural sciences during the second half of the 19thcentury. Instead, I argue that alternative conceptual frameworks were cultivated within German philology – concepts that were taken up in broader disciplinary debates, though they were not narrowly the products of them. (shrink)