Never increase, beyond what is necessary, the number of entities required to explain anything.

The explanation requiring the fewest assumptions is most likely to be correct.

Whenever two hypotheses cover the facts, use the simpler of the two.

Entities are not to be multiplied beyond necessity.

For nothing ought to be posited without a reason given, unless it is self-evident (literally, known through itself) or known by experience or proved by the authority of Sacred Scripture.

What can be explained by the assumption of fewer things is vainly explained by the assumption of more things.

It is vain to do with more what can be done with less.