Explanation and Cognition

These essays draw on work in the history and philosophy of science, the philosophy of mind and language, the development of concepts in children, conceptual.

Explaining Explanation

It is not a particularly hard thing to want or seek explanations. In fact, explanations seem to be a large and natural part of our cognitive lives. Children ask why and how questions very early in development and seem genuinely to want some sort of answer, despite our often being poorly equipped to provide them at the appropriate level of sophistication and detail. We seek and receive explanations in every sphere of our adult lives, whether it be to understand why a friendship has foundered, why a car will not start, or why ice expands when it freezes. Moreover, correctly or incorrectly, most of the time we think we know when we have or have not received a good explanation. There is a sense both that a given, successful explanation satisfies a cognitive need, and that a questionable or dubious explanation does not. There are also compelling intuitions about what make good explanations in terms of their form, that is, a sense of when they are structured correctly

Polarographic study of cadmium 5-hydroxy 2-(hydroxymethyl) 4H-pyran-4-one complex

A polarographic study was performed on the products formed in the interaction of cadmium (II) with a 5-hydroxy 2-(hydroxymethyl) 4H-Pyran-4-one, using varying conditions of pH, supporting electrolytes, and concentrations. Measurements using the differential pulse method show that cadmium (II) exhibits a molar combining ratio of complexing agents to cation ranging from 1 to 1 to 3 to 1 depending on the pH and the supporting electrolyte employed

Parallel Hopfield Networks

We introduce a novel type of neural network, termed the parallelHopfield network, that can simultaneously effect the dynamics of many different, independent Hopfield networks in parallel in the same piece of neural hardware. Numerically we find that under certain conditions, each Hopfield subnetwork has a finite memory capacity approaching that of the equivalent isolated attractor network, while a simple signal-to-noise analysis sheds qualitative, and some quantitative, insight into the workings (and failures) of the system

Newspaper Article – Soldiers Unable to Read, Write Get Special Quick Schooling

An article published in the Albuquerque Journal on October 11, 1943 describing the soldier literacy training school at Fort Ontario in Oswego, New York.https://scholarworks.moreheadstate.edu/stu_1210th_fort_ontario/1009/thumbnail.jp

The Effect of Pressures up to 17,000 Atmospheres upon Some Colloidal Suspensions

In some work which was being conducted at Wesleyan during the past year, on the effect of pressures upon some living organisms, it was noticed that when the water containing these organisms was subjected to pressures of more than a few hundred atmospheres a turbidity was usually developed. This suggested that something in the solution was being precipitated by means of pressure. Upon inspection it was found that this was some of the colloidal constituents in the water, and it was desired to determine whether or not pressure alone would cause the precipitation of a pure colloidal suspension. A number of colloidal suspensions were chosen at random and subjected to pressures varying from a few atmospheres to 17,000 atmospheres

Inferring Relevance in a Changing World

Reinforcement learning models of human and animal learning usually concentrate on how we learn the relationship between different stimuli or actions and rewards. However, in real-world situations “stimuli” are ill-defined. On the one hand, our immediate environment is extremely multidimensional. On the other hand, in every decision making scenario only a few aspects of the environment are relevant for obtaining reward, while most are irrelevant. Thus a key question is how do we learn these relevant dimensions, that is, how do we learn what to learn about? We investigated this process of “representation learning” experimentally, using a task in which one stimulus dimension was relevant for determining reward at each point in time. As in real life situations, in our task the relevant dimension can change without warning, adding ever-present uncertainty engendered by a constantly changing environment. We show that human performance on this task is better described by a suboptimal strategy based on selective attention and serial-hypothesis-testing rather than a normative strategy based on probabilistic inference. From this, we conjecture that the problem of inferring relevance in general scenarios is too computationally demanding for the brain to solve optimally. As a result the brain utilizes approximations, employing these even in simplified scenarios in which optimal representation learning is tractable, such as the one in our experiment

Some Recent Developments in High Pressure Windows

The field of optical studies at high pressures has been limited to a range of a few thousand atmospheres not because glass would not withstand a higher pressure but because the proper window support had not been used in order to utilize the maximum strength of the glass

The Biology of the Marquesan Sardine, Sardinella marquesensis

Data and samples obtained in the Marquesas Islands from 1954 to 1960 form the basis of this report. Various morphological traits of the Marquesan sardine, Sardinella marquesensis, are described, and measures of their variation are given . These sardines were found mostly in bays with clear to slightly turbid and clear-green to brownish-green water and with substrate of sand, rock, coral rubble, or a combination of these. The composition of their stomach contents was very similar to that of plankton obtained in sardine habitats. Ten of the 35 species of fish taken with sardines in the seine are probable predators of the latter. Sardine behavior in the field, in captivity, and as tuna bait is noted. Parasites included hemiurid trematodes, camallanid nematodes, and an ergasilid copepod. Attainment of sexual maturity is estimated at a standard length of 84 mm. Spawning is believed to occur throughout the year. Between 1,000 and 8,000 ova are deposited at a single spawning. The sex ratio favored males. The abundance of Marquesan sardines appears to be inadequate to sustain commercial live-bait tuna vessels like those operating from California ports