: To what extent do moral judgments depend on conscious reasoning from explicitly understood principles? We address this question by investigating one particular moral principle, the principle of the double effect. Using web-based technology, we collected a large data set on individuals’ responses to a series of moral dilemmas, asking when harm to innocent others is permissible. Each moral dilemma presented a choice between action and inaction, both resulting in lives saved and lives lost. Results showed that: patterns of moral (...) judgments were consistent with the principle of double effect and showed little variation across differences in gender, age, educational level, ethnicity, religion or national affiliation and a majority of subjects failed to provide justifications that could account for their judgments. These results indicate that the principle of the double effect may be operative in our moral judgments but not open to conscious introspection. We discuss these results in light of current psychological theories of moral cognition, emphasizing the need to consider the unconscious appraisal system that mentally represents the causal and intentional properties of human action. (shrink)

One of the reasons why most of us feel puzzled about the problem of abortion is that we want, and do not want, to allow to the unborn child the rights that belong to adults and children. When we think of a baby about to be born it seems absurd to think that the next few minutes or even hours could make so radical a difference to its status; yet as we go back in the life of the fetus we (...) are more and more reluctant to say that this is a human being and must be treated as such. No doubt this is the deepest source of our dilemma, but it is not the only one. For we are also confused about the general question of what we may and may not do where the interests of human beings conflict. We have strong intuitions about certain cases; saying, for instance, that it is all right to raise the level of education in our country, though statistics allow us to predict that a rise in the suicide rate will follow, while it is not all right to kill the feeble-minded to aid cancer research. It is not easy, however, to see the principles involved, and one way of throwing light on the abortion issue will be by setting up parallels involving adults or children once born. So we will be able to isolate the “equal rights” issue and should be able to make some advance... (shrink)

The doctrine (or principle) of double effect is often invoked to explain the permissibility of an action that causes a serious harm, such as the death of a human being, as a side effect of promoting some good end. According to the principle of double effect, sometimes it is permissible to cause a harm as a side effect (or “double effect”) of bringing about a good result even though it would not be permissible to cause such a harm as a (...) means to bringing about the same good end. Does the principle of double effect play the important explanatory role that has been claimed for it? To consider this question, one must be careful to clarify just what the principle is supposed to explain. Three misinterpretations of the principle’s force or range of application are common. 1. To ensure that Double Effect is not misunderstood as principle issuing a blanket permission on causing any unintended harm that yields a benefit, applications must require that the agent seek to minimize the harm involved. 2. Since it is widely accepted that it is wrong to aim to produce harm to someone as an end, to rule this out is not part of double effect’s distinctive content. 3. Harms that were produced regretfully and only for the sake of producing a good end may be prohibited by double effect because they were brought about as part of the agent’s means to realizing the good end. (shrink)

To what extent do moral judgments depend on conscious reasoning from explicitly understood principles? We address this question by investigating one particular moral principle, the principle of the double effect. Using web-based technology, we collected a large data set on individuals' responses to a series of moral dilemmas, asking when harm to innocent others is permissible. Each moral dilemma presented a choice between action and inaction, both resulting in lives saved and lives lost. Results showed that: (1) patterns of moral (...) judgments were consistent with the principle of double effect and showed little variation across differences in gender, age, educational level, ethnicity, religion or national affiliation (within the limited range of our sample population) and (2) a majority of subjects failed to provide justifications that could account for their judgments. These results indicate that the principle of the double effect may be operative in our moral judgments but not open to conscious introspection. We discuss these results in light of current psychological theories of moral cognition, emphasizing the need to consider the unconscious appraisal system that mentally represents the causal and intentional properties of human action. (shrink)

This paper is reprinted in the book Machine Ethics, eds. M. Anderson and S. Anderson, Cambridge University Press, 2011.

In the Trolley Case, as devised by Philippa Foot and modified by Judith Jarvis Thomson, a runaway trolley is headed down a main track and will hit and kill five unless you divert it onto a side track, where it will hit and kill one.

There has been considerable discussion in the past about the assumptions and basis of different ethical rules. For instance, it is commonplace to say that ethical rules are defaults rules, which means that they tolerate exceptions. Some authors argue that morality can only be grounded in particular cases while others defend the existence of general principles related to ethical rules. Our purpose here is not to justify either position, but to try to model general ethical rules with artificial intelligence formalisms (...) and to compute logical consequences of different ethical theories. More precisely, this is an attempt to show that progress in non-monotonic logics, which simulates default reasoning, could provide a way to formalize different ethical conceptions. From a technical point of view, the model developed in this paper makes use of the Answer Set Programming (ASP) formalism. It is applied comparatively to different ethical systems with respect to their attitude towards lying. The advantages of such formalization are two-fold: firstly, to clarify ideas and assumptions, and, secondly, to use solvers to derive consequences of different ethical conceptions automatically, which can help in a rigorous comparison of ethical theories. (shrink)

In the Trolley Case (Figure 1), as devised by Philippa Foot and modified by Judith Jarvis Thomson, a runaway trolley (i.e. tram) is headed down a main track and will hit and kill five unless you divert it onto a side track, where it will hit and kill one.

In the Trolley Case (Figure 1), as devised by Philippa Foot and modified by Judith Jarvis Thomson, a runaway trolley (i.e. tram) is headed down a main track and will hit and kill five unless you divert it onto a side track, where it will hit and kill one.

In this book, the extend to which we can equip artificial agents with moral reasoning capacity is investigated. Attempting to create artificial agents with moral reasoning capabilities challenges our understanding of morality and moral reasoning to its utmost. It also helps philosophers dealing with the inherent complexity of modern organizations. Modern society with large multi-national organizations and extensive information infrastructures provides a backdrop for moral theories that is hard to encompass through mere theorising. Computerized support for theorising is needed to (...) be able to fully grasp and address the inherent complexity. Using moral reasoning capacity will help us addressing the challenges that technological artefacts pose. They do not only contain information about us, they start to act on our behalves.With the increasing autonomy comes an increased need to ensure that their behaviour is in line with what we expect from them. To investigate and address these issues a laboratoy for philosophy is outlined: SophoLab. It consists of a methodology; a framework of modal logic, DEAL; and multi-agent software systems. SophoLab provides the basis for an experimental, computational philosophy. Its viability and usefulness are demonstrated through several experiments. (shrink)