Connectionist models provide a promising alternative to the traditional computational approach that has for several decades dominated cognitive science and artificial intelligence, although the nature of connectionist models and their relation to symbol processing remains controversial. Connectionist models can be characterized by three general computational features: distinct layers of interconnected units, recursive rules for updating the strengths of the connections during learning, and “simple” homogeneous computing elements. Using just these three features one can construct surprisingly elegant and powerful models of (...) memory, perception, motor control, categorization, and reasoning. What makes the connectionist approach unique is not its variety of representational possibilities or its departure from explicit rule-based models, or even its preoccupation with the brain metaphor. Rather, it is that connectionist models can be used to explore systematically the complex interaction between learning and representation, as we try to demonstrate through the analysis of several large networks. (shrink)

This article depends on much else that I have written elsewhere. Most of it has long since become public property, but some is recent enough to have gone unnoticed. My recent book, The Book of Revelation,1 devotes two chapters to Olivi as an exegete. Some of what I will say in the early part of this article is also presented there, because my aim in these chapters of the book was to show that the locus for Olivi's development of an (...) apocalyptic program was not simply his Revelation commentary but his exegesis as a whole. be it of Isaiah, Matthew, Job, Genesis or John. In fact, his threefold division of church history in line with Christ's three advents, which is featured in his... (shrink)

To understand the number sense, we need to understand its function. We argue that numerosity estimation is fundamental not only for perception, but also preparation and control of action. We outline experiments that link numerosity estimation with action, pointing to a generalized numerosity system that serves both perception and action preparation.

A great deal of attention has been paid to Petrus Iohannis Olivi’s last great work, his Apocalypse commentary. Less has been paid to his earliest writings. Here I want to address two aspects of those earlier works that rank among Olivi’s more interesting ideas. The first is the notion of Christ’s three advents in history: first in the flesh, then in the spirit, and finally in judgment. I mentioned those three advents years ago in my book on Olivi’s Apocalypse commentary, (...) but only briefly. Here I want to look more closely at the original context in which the three advents appeared.Second, I intend to examine the connection between the three advents and another of Olivi’s important ideas, that of the double... (shrink)

It is hardly news that medieval Joachism was a protean affair. Ever since Marjorie Reeve wrote, we have been aware that various people who valued Joachim did so for different reasons and, in the process, read him in different ways. They still do, and the different readings of Joachim offered today are hardly unrelated to the varieties of intepretation offered then. The important thing for our purposes is that, within a century after Joachim’s death, various intellectually adventurous souls in western (...) Europe were appropriating what we might reasonably describe as Joachite thought in a variety of ways, often without any indication that they recognized a connection between what they were saying and... (shrink)

Saccadic eye movements create (at least) two related but distinct problems for the visual system: they cause rapid image motion and a displacement of the retinal image. Although it is often assumed that the motion is too fast to be resolved, this is certainly not the case for low-spatial-frequency images. Recent experiments have suggested that the reason we are unaware of the motion during saccades is because motion channels are selectively suppressed, possibly by suppression of the magno-cellular (but not the (...) parvocellular) pathway. This suppression may explain why there is no sensation of motion during saccades, but it leaves open the problem of perceiving a stable world despite continual image displacements. (shrink)

One might assume that reviewing the revised edition of a book published in 1999 would be a simple task, but it is not, even if we avoid immersing ourselves in an examination of whether a revised issue was justified. The real question is whether in producing it Karris gives us something worth reading, something that makes us see the Admonitions as worth reading. The short answer is yes, certainly. Karris’s commentary on each admonition proceeds by presenting parallels. In speaking of (...) “parallels” rather than “sources” Karris, following New Testament scholar Daniel J. Harrington, recognizes that apparent similarities may result, not from direct borrowing, but from a common cultural milieu.... (shrink)