 Prior Plausibility. A final truism: new evidence for a theory has to be weighed against the theory’s prior plausibility. Maybe the theory is inherently implausible, being convoluted or metaphysically fraught. Or maybe the theory had become implausible because it clashed with earlier evidence. Or maybe the theory was already pretty plausible, being elegant and fitting well with previous evidence. In any case, the new evidence has to be evaluated in light of these prior considerations.