Evidence and a cumulative case for God › Why Swinburne places weight on simplicity

Evidence needs to be assessed alongside a hypothesis's prior probability. Swinburne gives simplicity a substantial role in that assessment. A hypothesis that postulates fewer entities, fewer kinds of entities, and fewer arbitrary limits can, on his account, deserve a higher prior than a more complicated rival, other things equal.

He argues that one divine person with unlimited power and knowledge is a simple explanatory proposal. A specified finite limit would invite a question about why the limit occurs at that particular point. His argument treats unlimited attributes as avoiding such arbitrary specification. This is a claim about explanatory description, not about physical size.

The proposal is contestable. A short phrase need not describe a metaphysically simple entity, and positing an agent with knowledge and intentions can seem to introduce substantial explanatory commitments. A critic can ask whether Swinburne's measure favors theism because it already accepts a controversial account of persons and properties.

There is a further question about why simplicity should track probability in an ultimate explanation. In familiar cases, we may have experience with successful and unsuccessful explanations. The existence of the universe provides a different setting. Swinburne argues for applying general explanatory criteria there; a reader must assess the extension, rather than assume that a familiar preference automatically settles it.

This is why the argument's dispute cannot be reduced to arithmetic. People could accept the same probability rules while disagreeing about the simplicity of theism, the available rivals, or the range of possible divine choices. A successful mathematical update would not independently vindicate the philosophical inputs.