of parsimony

The Principle "of parsimony" infers that a phenomena can be explained best with the simplest hypothesis that accounts for all the evidence. Since we can only tell the difference between something that is true and something that is false, by inferring our own observations and using the general rule to make a guess, adding entities to a hypothesis that are not accounted for by evidence results in a hypothesis that is not parsimonious and less believable than prior.

This is referred to and explained in Occam's Razor, which follows the same basic principle.

The word may also be used to infer simplicity, or the state of a hypothesis in which it explains a phenomenon using entities suggested by evidence, and no absolutely more.

"Your hypothesis for insert phenomena, i.e.gravitational effects derived from atomic warp of spacetime was fine until you added entity to it, we have no evidence for that, you're just making stuff up, we observed the electromagnetic fluctuation before in CERN, why do you need to make it more complex, just do the math and see if it works, trust me it seems accurate enough already. Just apply the Principle of parsimony!"