The paper analyzes how and under which assumptions it is possible to compare (in a relationist setting and relatively to qualities) entities living in different worlds. We begin with a standard technique to construct quality kinds via an abstraction process. In the first case, the process is applied across all the possible worlds and we show that the resulting quality system has problematic con...

Recently, the relationship between several forms of default reasoning based on conditional defaults has been investigated. In particular, the systems based on ε-semantics, preferential models, and (fragments of) modally-defined conditional logics have been shown to be equivalent. These systems form a plausible core for default inference, but are too weak in general, failing to deal adequately w...

This paper presents a solution in a first-order monotonic logic to a simplified version of the Surprise Birthday Present Problem, a challenge problem for the formal commonsense reasoning community. The problem concerns two siblings who wish to surprise their sister with a present for her birthday: the aim is to construct a theory that will support the desired inferences, not allow undesired inf...

Probabilistic logic programs have primarily studied the problem of entailment of probabilistic atoms. However, there are some interesting applications where we are interested in finding a possible world that is most probable. Our first result shows that the problem of computing such ”maximally probable worlds” (MPW) is intractable. We subsequently show that we can often greatly reduce the size ...

It could be that, at the moment you finish reading this essay, the entire universe is wiped out in a great cosmic reset. After the reset, events exactly like those of the past 14 billion years are replayed. You and I and everyone we know have doppelgänger echoes in the very distant future. Call this scenario First. Here’s a different way things could be: this could have already happened. That i...

recent findings in stem cell biology have opened a new window in regenerative medicine. the endometrium possesses mesenchymal stem cells (mscs) called endometrial stem cells (enscs) having specific regenerative properties linked to adult stem cells. they contribute in tissue remodeling and engineering and were shown to have immuno-modulating effects. many clinical trials were undertaken to asce...