LISP: An introduction and some great programs

Some of the advantages of LISP and some of its unsavory reputation are discussed. Some LISP programs in a variety of areas (chemistry, medicine, question answering, natural language, mathematics, airline tariffs, etc.) are briefly described.     

A representation theorem for languages with generalized quantifiers through back-and-forth methods

We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.     

Truthlikeness without truth: A methodological approach

In this paper, an attempt is made to solve various problems posed to current theories of verisimilitude: (1) the (Miller's) problem of linguistic variance; (2) the problem of which are the best scientific methods for getting the most verisimilar theories; and (3) the question of the ontological commitment in scientific theories. As a result of my solution ot these problems, and with the help of other considerations of epistemological character, I conclude that the notion of Tarskian truth is dispensable in a rational (and realist) interpretation of the scientific enterprise. As a logical result, however, falsificationism will be vindicated.

... and in brief, a speaker must always aim at verisimilitude, and send the truth packing.

Plato,Phaedrus, 272 EI want to express my gratitude to Professors García-Bermejo, Niiniluoto, and Zofío for interesting comments and critiques of several of the ideas in this paper, and to Miss Karen Firnich for correcting my English. I am also thankful to an anonymous referee who indicated several dark points on a previous version of my article.     

Patient variable biases in clinical judgment: conceptual overview and methodological considerations

Specific conceptual factors are presented as having contributed to the negative findings of past psychotherapy bias research. Among these factors are the restrictive nature of both the definition of bias and the model of the biased clinician. A review of published studies of several patient variable biases (e.g., gender, race/ethnicity, and age) indicated that bias may best be defined in broader terms and that its occurrence may be more circumscribed than originally conceived. In addition, the lack of a theoretical perspective in this area of research is noted and the applicability of some social cognitive processes is discussed. Methodological factors are also considered, and recommendations for future research are offered.     

Visual perception of surface curvature: psychophysics of curvature detection induced by motion parallax

The continuous approach to optic-flow processing shows that the curvature of a moving surface is related to a second spatial derivative of the velocity field, the spin variation (Droulez & Cornilleau-Pérès, 1989). With this approach as a theoretical framework, visual sensitivity to the curvature of a cylinder in motion was measured using a task of discrimination between cylindrical and planar patches. The results confirm the predictions suggested by the theory: (1) Sensitivity to curvature was always greater when the cylinder axis and the frontal translation were parallel than when they were orthogonal. The ratio of curvature detection thresholds in the two cases was between 1.3 and 2.5; the value predicted from the spin variation theory is about 2. (2) Sensitivity to curvature increased strongly with the velocity of the motion but was only weakly affected by its amplitude and the duration of viewing for the range of values used in our experiments.     

Response to commentaries on “A neurobiological model for near-death experiences”

This work has received financial support from FONDECYT (Project 1111-88). The authors also acknowledge the helpful comments of Dr. Bruce Cassels.     

Social structure features in three inbred strains of mice, C57Bl/6J, Balb/cj, and NIH: a comparative study

Some features of social living were investigated in three inbred strains of mice: C57Bl/6j, Balb/cj, and NIH. Five social behaviors--Aggression, Submission, Allogrooming, Social Rest and Rest Alone, as well as Wheel Running Activity--were recorded 2 h daily for a week, in 26 groups of seven male mice living in an enriched environment. Dominants and subordinates among strains shared some behavioral characteristics, but strain contributions upon social structure were also detected. Similarities among strains included the appearance of a single dominant mouse per group rated as the most aggressive, besides from being the animal presented with most Submissions. Allogrooming was more frequent among subordinates than among dominants and subordinates. Differences among strains were that agonistic behavior among subordinates was higher in the Balb/cj and NIH groups than in the C57Bl/6j mice. NIH mice were recorded in Rest Alone more often than mice from the other strains. C57Bl/6j dominants showed higher rates of Wheel Running Activity than subordinates.