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.

Of two equivalent theories or explanations, all other things being equal, the simpler one is to be preferred.

No more things should be presumed to exist than are absolutely necessary.

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

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.

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