In a recent discussion, Earman and Norton [(1998)] propose a classification of supertasks that generate indeterminism which is flawed. An emendation is presented here.

The paper shows a new example of nonuniqueness of the solutionto Newtonian equations of motion for infinite gravitational systems. Unlike otherexamples, the gravitational field presents no singularity, nor are the non-gravitational forcesintroduced in the model singular (in particular, there are no collisions). The result is also ofinterest because it points to an interesting limitation of the elementary (Newtonian) formulationof classical mechanics.

The examples of dynamic supertasks analyzed to date in the philosophical literature, in which both determinism and the classical laws of conservation of energy and momentum are violated, all share the important limitation of requiring material systems of infinite mass. This paper demonstrates that this limitation is not necessary. This has important consequences for the scope and meaning of such violations.

The paper shows a new example of nonuniqueness of the solutionto Newtonian equations of motion for infinite gravitational systems. Unlike otherexamples, the gravitational field presents no singularity, nor are the non-gravitational forcesintroduced in the model singular (in particular, there are no collisions). The result is also ofinterest because it points to an interesting limitation of the elementary (Newtonian) formulationof classical mechanics.

The paper presents a new paradox in the sphere of the classical mechanics of infinite systems. The paradox, which implies the existence of an interaction at a distance as well as gravitation, would seem to require an extension of the concept of mechanical explanation. However, it is not clear how such an extension might be carried out.

The paper presents a new paradox in the sphere of the classical mechanics of infinite systems. The paradox, which implies the existence of an interaction at a distance as well as gravitation, would seem to require an extension of the concept of mechanical explanation. However, it is not clear how such an extension might be carried out.

In this article I propose what I call the inverse spaceship paradox. The article's interest lies in the fact that, contrary to what appears to be an implicit agreement in the literature on indeterminism, it shows that coming from infinity can be a perfectly predictable and therefore deterministic process in a classical universe.