Entities are not to be multiplied beyond necessity.

3 is a prime, 5 is a prime, and 7 is a prime. Why bother with non-prime numbers when the primes can do everything?

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

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

Intuitive cognition of a thing is cognition that enables us to know whether the thing exists or does not exist, in such a way that, if the thing exists, then the intellect immediately judges that it exists and evidently knows that it exists, unless the judgment happens to be impeded through the imperfection of this cognition.

Entities should not be posited unnecessarily.

With all things being equal, the simplest explanation tends to be the right one.