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Mental image rotation, used in processing rotated scenes or stimuli, is a good indicator of the status of one's visual intelligence. Measurement of this spatial ability is a sensitive indicator of cognitive damage, for example, in those who have been chronically exposed to industrial organic solvents and other neurotoxins. In order to ascribe incurred damage to specific stages of spatial processing, a precise model for the temporal events of mental rotation is required. The goal of this research was to take a first step in defining such a model, by analyzing the temporal build-up of stimulus knowledge during mental image rotation. When presented with a single, rotated alphanumeric character which must be identified as being either normal or mirror-reversed, mental rotation actually consists of several subprocesses. In addition to image rotation: initial determinations of stimulus identity, approximate orientation, and rotation direction. Information gained from these subprocesses may build continuously over time, or may build in a more discrete fashion as encoded stimulus information is operated upon. Two experiments were conducted, applying Meyer et al.'s (1985) reaction-time (RT) measurement procedure and Smith et al.'s (1982) analysis methodology to determine which of these two model types may best describe the information build-up during the processing of a rotated stimulus. A normal or mirror-reversed rotated character served as a priming stimulus for a second, upright test stimulus. With valid primes, a strategy of image rotation was required to adequately prepare a response for identifying the test stimulus. RTs to determine whether the test stimulus was normal or mirror-reversed were measured, and the shapes of subsequent RT distributions were compared. By modeling the statistical power of the analysis along with the results of the response-priming procedure, there was a clear indication that temporal information build-up across the subprocesses of mental rotation is not all-or-none. Instead, partial information is available from one or more subprocesses, suggesting that an entirely discrete model of these events is not appropriate.

Brightman defines reason as the ideal function of experience that brings the disparate elements given in experience into inclusive, systematic harmony. Lewis defines reason as consistency in attitude and in prepared manner of response to the situations in which the doer finds himself. Both thinkers agree that reason can be used to make true value judgments and good value choices, despite some differences in their analysis of valuation. Brightman holds that value-claims, or what is thought to be good, must be tested by norms which are themselves principles for the coherent organization of such claims. Lewis also speaks of valuations as value-claims, but adds that goodness is an objective quality of objects given in experience that no criticism can wholly remove. For Brightman, a rational value-choice is one that contributes to the organization of all value-claims in an internally harmonious pattern that ultimately involves fruitful interaction with other persons and with the total environment of the individual. But Lewis holds that value-choices will be rational (or right) when they conform with rules of consistent doing and such choices will be intelligible (or good) when they include an appraisal of the value potentialities of the objective situation in which the doer finds himself. Despite initial differences in value analysis, both thinkers agree that the summum bonum is a life of consistently chosen and coherently organized valuations which all persons ought to choose. Their common view of the good life seems open to two objections: (a) one may prefer intrinsic values other than the ideal of coherently chosen values without moral disapprobation; and (b) the use of "ought" can mean either what is fitting or what is a duty to do in a situation, and these two meanings do not always coincide as they suggest. Brightman and Lewis hold that the content of moral rightness consists of what is both objectively good and in conformity with the principle of universalization. This view is open to the objections that: (a) it makes duty consist of whatever is thought to be objectively good, rather than 11hat is objectively right; (b) it makes it impossible to settle a conflict between duties, where such a conflict is not about some good end but is about which alternative course of action is morally right; and (c) being under a specific obligation seems a different kind of experience from valuing something. Toulmin is concerned with establishing the validity of the use of argument in ethical disputes so that "good" or sufficient reasons can be found to terminate such disputes. The "good reasons" approach essentially consists of the derivation of criteria for evaluation from a given field of discourse in which arguments first arise. Toulmin found only two ways in which ethical arguments can be terminated. First, an argument about the rightness of an act can be terminated if the act in question is found to conform with the moral code of the community. Secondly, an argument about the goodness of a moral rule can be terminated by asking if the rule in question contributes to the fecundity of the community. Two criticisms have been made of the ideal utilitarian context in which Toulmin discusses ethical reasoning: (a) the use of the principle of fecundity to terminate arguments about moral rules functions as a definition of goodness and rightness and as such is open to the objections made against utilitarianism--objections that Toulmin does not consider; and (b) his dismissal of the deontological point of view as "primitive" is not entailed by the "good reasons" approach to ethics and so the deontologist may find good reasons for rejecting utilitarianism.