HOW DOES THE TEILHARDIAN VISION OF EVOLUTION COMPARE WITH CONTEMPORARY THEORIES?

Abstract. Teilhard de Chardin's ideas about the mechanisms of biological evolution are revised and their connections with contemporary theories are reported. Teilhard de Chardin's main contribution is the proposal of a new scientific discipline, geobiology—the science of the biosphere evolving as a whole. The main fields of interest of geobiology are reported, and its relationships with contemporary hypotheses, such as Lovelock's Gaia, are discussed. The consequences of this kind of approach are the parallel evolution described as orthogenesis and the presence of canalization phenomena. These Teilhardian hypotheses are discussed in relation to those of the process structuralists and to the novelties of the molecular evolution of the genome. Conclusions are that the mechanisms discussed by Teilhard are presently taken into consideration by contemporary evolutionists in order to construct a new theory of biological evolution.     

AN EXPLOSION OF DAZZLING FLASHES: TEILHARD'S UNITY OF FAITH AND SCIENCE

Abstract. Science and revelation have been presented as two books with the same “author,” their reconciliation being called “concordism.” Teilhard opposed concordism, insisting that supposed “revelations” be treated as scientific hypotheses to be verified or not in experience. Applying his criterion for truth (Does it bring “coherence and fecundity” to the phenomena?) to Christian revelation, he told of finding “an explosion of dazzling flashes.” So Teilhard spoke of the hypothesis as the supreme spiritual act wherein the dust of experience takes on form and is kindled at the fire of knowledge.     

Parameters for vowel substitutions in Broca''s aphasia

Most phonological investigations of aphasic speech have focused on consonants. In this study, the vowel substitutions of five English-speaking Broca's aphasics were investigated with respect to several major explanatory hypotheses. An important possible motivating factor for aphasic substitutions, phonological environment, is an unlikely origin for these errors, since most substitutions occur along the paradigmatic axis. Another prominent hypothesis, markedness, also has no predictive power for the data of this sample. However, an analysis of the five Chomsky and Halle (1968, (The Sound Pattern of English), New York: Harper and Row) vowel features indicates that the two features for vowel height are selectively impaired: There is a strong tendency for lower vowels to replace higher targets. Moreover, the substitution sounds tend to be close to their target sounds along the height axis. Four possible hypotheses are advanced to account for this consistent lowering tendency.     

Statistical significance tests for binormal ROC curves

Statistical significance tests are derived and evaluated for measuring apparent differences between an obtained and an expected binormal ROC curve, between two independent binormal ROC curves, and among groups of independent binormal ROC curves. A binormal ROC curve is described by two parameters which represent the spread of the means and the ratio of the standard deviations of the two underlying Gaussian decision variable distributions. To test the significance of apparent differences between or among ROC curves, approximate χ² statistics for each of the three tests were constructed from maximum likelihood estimates of the two parameters defining the binormal ROC curve. The performance of each test statistic was evaluated by simulating five-category rating scale data with equal numbers of noise and signal-plus-noise trials (set at 50, 250, and 500) for each of three typical ROC curves. For the significance test involving only one ROC curve, rating scale data were generated from the chance diagonal of the ROC space also. Although test performance was found to be somewhat dependent on the number of trials and on the location of the ROC curve in the ROC space, comparisons of the obtained and expected fractions of (falsely) significant results at various α levels showed the proposed statistical significance tests to be reliable under practical experimental conditions.     

Studies in social influence: V. Minority influence and conversion behavior in a perceptual task

The effects of influence attempts by a majority and by a minority were examined on both a manifest response level and a latent perceptual level. Female subjects were exposed to a series of blue slides that were consistently labeled as green by a female confederate. The confederate was presented as a member of either a majority or a minority. On each trial, subjects were required to indicate the color of the slide presented and the color of the afterimage perceived on a white screen following removal of the slide. It was predicted that (a) the subject's judgment of the chromatic afterimage would be modified when the influence agent represented a minority, and (b) this modification will be more pronounced when the source of influence is absent than when it is present. The results supported the prediction in both the main study and its replication.     

Cortical stimulation and speech timing: A preliminary observation

Audio recordings of the speech of seven patients receiving cortical stimulation during epilepsy surgery were acoustically analyzed, and duration measurements of the sound /s/ under stimulation and nonstimulation conditions were compared. It was found that in the dominant hemisphere, stimulation tended to significantly increase the duration of /s/; but not all stimulation sites were comparably affected. Stimulation of frontal lobe locations was also observed to more frequently result in durational increases than when temporal or parietal sites were stimulated. However, for sites affected, the actual magnitude of durational increase was comparable among the three lobes.