How to modify the strength of a reason

Kearns and Star have previously recommended that we measure the degree to which a reason supports conclusion, either about how act or what believe, as conditional probability of conclusion given reason. I show properly formulate this recommendation allow for dependencies among considerations being aggregated. This formulation allows us account considerations, do not themselves favour specific can modify strength thus explain intensifiers attenuators described by Dancy. The also accounts workings partial undercutters in epistemology. then my avoids counterexamples Brunero levied against probability-based theories strengths reasons. My theory, suggested Star, reasons are measured probabilities. If is successful, it will count idea on same scale