Obligation is displayed toward rules or requirements of formalized roles stemming from membership in society, whereas loyalty is shown to persons and is founded upon communal commitment to them. Loyalties entail obligations, but the converse does not necessarily hold. While one may have obligations toward everyone, it is neither conceptually nor psychologically possible to be loyal to all perso...

In this paper an extension of the IFAD VDM-SL Toolbox with a proof obligation generator is described. Static type checking in VDM is undecidable in general and therefore the type checker must be incomplete. Hence, for the “difficult” parts introducing undecidability, it is up to the user to verify the consistency of a specification. Instead of providing error messages and warnings, the approach...

The actions and decisions taken by the present generation will affect not only the welfare but also the composition of future generations. A number of authors have used this fact to bolster the conclusion that the present is only weakly obligated to provide for future welfare since in choosing between futures of poverty and abundance, we are not deciding the welfare of a welldefined group of fu...

We recently introduced p-automata, automata that read discrete-time Markov chains and showed they provide an automata-theoretic framework for reasoning about pCTL model checking and abstraction of discrete time Markov chains. We used turn-based stochastic parity games to define acceptance of Markov chains by a special subclass of p-automata. Definition of acceptance required a reduction to a se...

It is often thought that judgments about what we ought to do are limited by judgments about what we can do, or that "ought implies can." We conducted eight experiments to test the link between a range of moral requirements and abilities in ordinary moral evaluations. Moral obligations were repeatedly attributed in tandem with inability, regardless of the type (Experiments 1-3), temporal duratio...

In contemporary medical ethics health is rarely acknowledged to be an ethical obligation. This oversight is due to the preoccupation of most bioethicists with a rationalist, contract model for ethics in which moral obligation is limited to truth-telling and promise-keeping. Such an ethics is poorly suited to medicine because it fails to appreciate that medicine's basis as a moral enterprise is ...

During meiosis, crossing-over--the exchange of genetic material between maternal and paternal chromosomes--is stringently controlled to restrict the number of crossovers per chromosome pair. In this issue of Cell, Martini et al., (2006) report that the reduction of crossover-initiating events does not result in fewer crossovers. These results have important implications for our understanding of...

Driving is a complex task, yet some people with dementia are capable of driving safely. As driving a vehicle is a privilege and not a right, clinicians are often called upon to provide guidance regarding their patients' ability to drive safely. The Australian Bureau of Statistics has predicted that by 2056, one in four Australians will be aged over 65. Older members of our community are increas...