This article asks whether our moral duties are created by others’ non-compliance and whether we should fulfill them or not. For example, do we need to donate more of our income to eradicate world poverty because billionaires do not donate? If so, how much should we donate? In short, should we make up for others’ defaulting on their moral duties – and if so, how and to what extent? Such situations are called non-ideal circumstances in political philosophy. With the increasing (...) importance of non-ideal theories of justice and ethics, the question of how we should act in non-ideal situations has received more attention in the ethics literature in recent years. This article poses and addresses the question of whether we should take up the slack when others do not comply with their own moral duty. This article examines how consequentialism and contractualism might respond to non-ideal situations of taking up the slack and then defends a contractualist-constructivist approach to dealing with these situations. (shrink)

When dissimilar images are presented to the two eyes, binocular rivalry (BR) occurs, and perception alternates spontaneously between the images. Although neural correlates of the oscillating perception during BR have been found in multiple sites along the visual pathway, the source of BR dynamics is unclear. Psychophysical and modeling studies suggest that both low- and high-level cortical processes underlie BR dynamics. Previous neuroimaging studies have demonstrated the involvement of high-level regions by showing that frontal and parietal cortices responded time locked (...) to spontaneous perceptual alternation in BR. However, a potential contribution of early visual areas to BR dynamics has been overlooked, because these areas also responded to the physical stimulus alternation mimicking BR. In the present study, instead of focusing on activity during perceptual switches, we highlighted brain activity during suppression periods to investigate a potential link between activity in human early visual areas and BR dynamics. We used a strong interocular suppression paradigm called continuous flash suppression to suppress and fluctuate the visibility of a probe stimulus and measured retinotopic responses to the onset of the invisible probe using functional MRI. There were ∼130-fold differences in the median suppression durations across 12 subjects. The individual differences in suppression durations could be predicted by the amplitudes of the retinotopic activity in extrastriate visual areas (V3 and V4v) evoked by the invisible probe. Weaker responses were associated with longer suppression durations. These results demonstrate that retinotopic representations in early visual areas play a role in the dynamics of perceptual alternations during BR. (shrink)

Metacontrast is a visual illusion in which the visibility of a target stimulus is virtually lost when immediately followed by a nonoverlapping mask stimulus. For a colored target, metacontrast is color-selective, with target visibility markedly reduced when the mask and target are the same color, but only slightly reduced when the colors differ. This study investigated neural correlates of color-selective metacontrast for cone-opponent red and green stimuli in the human V1, V2, and V3 using functional magnetic resonance imaging. Neural activity (...) was suppressed when the target was rendered less visible by the same-colored mask, and the suppression was localized in the cortical region retinotopically representing the target, correlating with the perceptual topography of visibility/invisibility rather than the physical topography of the stimulus. Retinotopy-based group analysis found that activity suppression was statistically significant for V2 and V3 and that its localization to the target region was statistically significant for V2. These results suggest that retinotopic color representations in early visual areas, especially in V2, are closely linked to the visibility of color. (shrink)

In the bitcoin whitepaper, Satoshi Nakamoto (2008: 2) defines an electronic coin as a chain of digital signatures. Many have since defined a bitcoin as a chain of digital signatures. This latter definition continues to appear in reports from central banks, advocacy centers, and governments, as well as in academic papers across the disciplines of law, economics, computer science, cryptography, management, and philosophy. Some have even used it to argue that what we now call bitcoin is not the real (...) bitcoin. The definition fails, however. This is important because the Chain Definition obscures Satoshi’s solution to a dilemma in the design of electronic cash, as well as the truth about bitcoin’s privacy and fungibility. In this article, I explain why the Chain Definition fails and what Satoshi likely endorsed instead. Along the way, I untangle some issues around bitcoin fungibility and clarify some others around the ontology of digital assets. (shrink)

On 26 July 2016, Satoshi Uematsu murdered 19 and injured 26 at a caregiving facility in Sagamihara, Japan, making it the country’s worst mass killing since WWII. In this article, I offer an analysis of the Sagamihara 19 massacre. I draw on the work of Julia Kristeva and Emmanuel Levinas to argue that claims about disability experience are insufficient to justify normative projects. In short, disability is normatively ambiguous.