Interactions in the discrimination and absolute judgement of orientation and length

An asymmetric model is described for interactions in the perception of two dimensions (length and orientation) of a single visual stimulus. Two methods were used to test these interactions, and models for the interpretation of the possible outcomes of these tests are discussed. A length discrimination task showed facilitation (decreased reaction time) when orientation was covaried with length, and interference (increased reaction time) when random orientation variation was introduced. A smaller effect was seen when length was varied in an orientation discrimination task in a correlated or random fashion. Analysis of sequential effects showed that reaction times are fastest on repetition trials and are slowed by either the need to change the response or the need for additional sensory processing. With the second method, it was found that the amount of information transmitted in the estimation of orientation was not affected by the introduction of the redundant dimension of length, but that there was a significant gain in the amount of information transmitted in the estimation of length by the addition of the redundant dimension of orientation. It is concluded that orientation is probably a perceptual primitive of the visual system whereas length is a computed variable.     

Defending the Democratic Argument for Limitarianism: A Reply to Volacu and Dumitru

In this paper, I argue that limitarian policies are a good means to further political equality. Limitarianism, which is a view coined and defended by Robeyns (2017), is a partial view in distributive justice which claims that under non-ideal circumstances it is morally impermissible to be rich. In a recent paper, Volacu and Dumitru (2018) level two arguments against Robeyns’ Democratic Argument for limitarianism. The Democratic Argument states that limitarianism is called for given the undermining influence current inequalities in income and wealth have for the value of democracy and political equality. Volacu and Dumitru’s Incentive Objection holds that limitarianism places an excessive and inefficient burden on the rich in ensuring political equality. The Efficacy Objection holds that even if limitarianism limits excessive wealth it still fails to ensure the preservation of political equality. In this paper, I will argue that both of these objections fail, but on separate grounds. I argue that the Incentive objection fails because one could appeal to limitarian policies that are different from the ones discussed by Volacu and Dumitru and which escape the problem of reduced productivity. I argue against the Efficacy Objection that limitarian policies are a partial but highly valuable step towards establishing political equality, and that they can and should complement or be complemented by other strategies.

     

The Semantics of Fictional Names

Abstract: In this paper we defend a direct reference theory of names. We maintain that the meaning of a name is its bearer. In the case of vacuous names, there is no bearer and they have no meaning. We develop a unified theory of names such that one theory applies to names whether they occur within or outside fiction. Hence, we apply our theory to sentences containing names within fiction, sentences about fiction or sentences making comparisons across fictions. We then defend our theory against objections and compare our view to the views of Currie, Walton, and others.