Michael-Thomas Liske

Potentiality in Rationalism

A potential can be understood as the capacity of an individual substance to advance in virtue of its inner nature—given suitable external conditions—to a genuinely new state, a development which is grounded in the original constitution of its subject but is not necessitated by it. This presupposes a plurality of independent substances, in order to contrast the inner basis of development with its external conditions. Furthermore, genuine possibilities must be acknowledged which for ever remain unrealised. Therefore in Spinoza, who does not allow for anything beyond the actual way of existing or a single all-encompassing substance, a potential can only be a useful description of phenomena, e.g. of how the distribution of active power over individuals can vary. Descartes too, atomising temporal existence into unconnected moments, cannot recognise an identically persisting substance and its dispositions to develop following inner laws. Substance must be created continually anew. Nearest to the conception of a true potential is Leibniz’s notion of primitive metaphysical force. As a capacity, enhanced by striving, it stands between potency and act. Being the permanent basic tendency of striving or the law which determines the whole succession of perceptual states in a way characteristic for the individual it constitutes individuality. On the other hand, Leibniz’s determinism includes the assumption: Everything that ever happens to the individual is at any time given in the individuals present state. One might object, however, that a potential in a significant sense enables a development which transcends the status quo and does not merely unfold what is already preformed in the present state.