The norm of assertion: Empirical data

Assertions are speech acts by means of which we express beliefs. As such they are at the heart of our linguistic and social practices. Recent research has focused extensively on the question whether the speech act of assertion is governed by norms, and if so, under what conditions it is acceptable to make an assertion. Standard theories propose, for instance, that one should only assert that p if one knows that p (the knowledge account), or that one should only assert that p if p is true (the truth account). In a series of four experiments, this question is addressed empirically. Contrary to previous findings, knowledge turns out to be a poor predictor of assertability, and the norm of assertion is not factive either. The studies here presented provide empirical evidence in favour of the view that a speaker is warranted to assert that p only if her belief that p is justified

Mens rea ascription, expertise and outcome effects: Professional judges surveyed

A coherent practice of mens rea (‘guilty mind’) ascription in criminal law presupposes a concept of mens rea which is insensitive to the moral valence of an action’s outcome. For instance, an assessment of whether an agent harmed another person intentionally should be unaffected by the severity of harm done. Ascriptions of intentionality made by laypeople, however, are subject to a strong outcome bias. As demonstrated by the Knobe effect, a knowingly incurred negative side effect is standardly judged intentional, whereas a positive side effect is not. We report the first empirical investigation into intentionality ascriptions made by professional judges, which finds (i) that professionals are sensitive to the moral valence of outcome type, and (ii) that the worse the outcome, the higher the propensity to ascribe intentionality. The data shows the intentionality ascriptions of professional judges to be inconsistent with the concept of mens rea supposedly at the foundation of criminal law

Nucleation of reaction-diffusion waves on curved surfaces

We study reaction-diffusion waves on curved two-dimensional surfaces, and determine the influence of curvature upon the nucleation and propagation of spatially localized waves in an excitable medium modelled by the generic FitzHugh-Nagumo model. We show that the stability of propagating wave segments depends crucially on the curvature of the surface. As they propagate, they may shrink to the uniform steady state, or expand, depending on whether they are smaller or larger, respectively, than a critical nucleus. This critical nucleus for wave propagation is modified by the curvature acting like an effective space-dependent local spatial coupling, similar to diffusion, thus extending the regime of propagating excitation waves beyond the excitation threshold of flat surfaces. In particular, a negative gradient of Gaussian curvature $\Gamma$, as on the outside of a torus surface (positive $\Gamma$), when the wave segment symmetrically extends into the inside (negative $\Gamma$), allows for stable propagation of localized wave segments remaining unchanged in size and shape, or oscillating periodically in size

The Content-Dependence of Imaginative Resistance

An observation of Hume’s has received a lot of attention over the last decade and a half: Although we can standardly imagine the most implausible scenarios, we encounter resistance when imagining propositions at odds with established moral (or perhaps more generally evaluative) convictions. The literature is ripe with ‘solutions’ to this so-called ‘Puzzle of Imaginative Resistance’. Few, however, question the plausibility of the empirical assumption at the heart of the puzzle. In this paper, we explore empirically whether the difficulty we witness in imagining certain propositions is indeed due to claim type (evaluative v. non-evaluative) or whether it is much rather driven by mundane features of content. Our findings suggest that claim type plays but a marginal role, and that there might hence not be much of a ‘puzzle’ to be solved

Analyzing critical propagation in a reaction-diffusion-advection model using unstable slow waves

The effect of advection on the critical minimal speed of traveling waves is studied. Previous theoretical studies estimated the effect on the velocity of stable fast waves and predicted the existence of a critical advection strength below which propagating waves are not supported anymore. In this paper, the critical advection strength is calculated taking into account the unstable slow wave solution. Thereby, theoretical results predict, that advection can induce stable wave propagation in the non-excitable parameter regime, if the advection strength exceeds a critical value. In addition, an analytical expression for the advection-velocity relation of the unstable slow wave is derived. Predictions are confirmed numerically in a two-variable reaction-diffusion model.Comment: 11 pages, 8 figure

Causation, foreseeability, and norms

A growing body of literature has revealed ordinary causal judgement to be sensitive to normative factors, such that a norm-violating agent is regarded more causal than their non-norm-violating counterpart. In this paper, we explore two competing explanations for this phenomenon: the Responsibility View and the Bias View. The Bias View, but not the Responsibility View, predicts features peripheral to the agent’s responsibility to impact causal attributions. In a series of three preregistered experiments (N = 1162), we present new evidence that the Norm Effect arises from such peripheral features, namely from nonpertinent or entirely silly norm violations. Furthermore, we show that this effect cannot be explained by recourse to the agent’s foreknowledge or desire of the outcome, nor by its foreseeability: the Norm Effect arises even when participants judge the norm-violating agent’s doing as equally foreseeable. This, we argue, provides evidence in favour of the Bias View

From OECD to India: Exploring cross-cultural differences in perceived trust, responsibility and reliance of AI and human experts

AI is getting more involved in tasks formerly exclusively assigned to humans. Most of research on perceptions and social acceptability of AI in these areas is mainly restricted to the Western world. In this study, we compare trust, perceived responsibility, and reliance of AI and human experts across OECD and Indian sample. We find that OECD participants consider humans to be less capable but more morally trustworthy and more responsible than AI. In contrast, Indian participants trust humans more than AI but assign equal responsibility for both types of experts. We discuss implications of the observed differences for algorithmic ethics and human-computer interaction

Reasonableness on the Clapham Omnibus: Exploring the outcome-sensitive folk concept of reasonable

This paper presents a series of studies (total N=579) which demonstrate that folk judgments concerning the reasonableness of decisions and actions depend strongly on whether they engender positive or negative consequences. A particular decision is deemed more reasonable in retrospect when it produces beneficial consequences than when it produces harmful consequences, even if the situation in which the decision was taken and the epistemic circumstances of the agent are held fixed across conditions. This finding is worrisome for the law, where the reasonable person standard plays a prominent role. The legal concept of reasonableness is outcome-insensitive: whether the defendant acted in a reasonable fashion or not depends exclusively on her context of action, no matter how things play out. Folk judgments of reasonableness are thus inconsistent with the legal concept of reasonableness. Problematically, in common law jurisdictions, the decision whether a defendant’s behavior was reasonable or not is frequently (though not necessarily) delegated to a lay jury