Abstract
We present a deductive theory of space-time which is realistic, objective, and relational. It is realistic
because it assumes the existence of physical things endowed with concrete properties. It is objective
because it can be formulated without any reference to cognoscent subjects or sensorial fields. Finally, it
is relational because it assumes that space-time is not a thing but a complex of relations among things.
In this way, the original program of Leibniz is consummated, in the sense that space is ultimately an
order of coexistents, and time is an order of succesives. In this context, we show that the metric and
topological properties of Minkowskian space-time are reduced to relational properties of concrete things.
We also sketch how our theory can be extended to encompass a Riemannian space-time.