How to rank evidence
Three main characteristics of evidence:
Directness (Direct vs. indirect)
Strength (Strong vs. weak)
Reliability (Reliable vs. unreliable)
Direct (D): Bears immediately on question at hand. If true, proves proposition. Necessary and sufficient.
Indirect (I): Bears on question related to question at hand (circumstantial evidence). Necessary but not sufficient. “Consistent with” or “indicative of” the question.
Strong (S): Objectively falsifiable; requires an object and expert opinion.
Weak (W): Not falsifiable; lacking a tangible record.
Reliable (R): Known to be correct.
Unreliable (U): Not known to be correct, i.e., known to be uncertain or wrong.
Ranking evidence
Strongest is DSR (direct, strong, reliable). Proves proposition.
Next-strongest is ISR (indirect, strong, reliable). Very common.
Weakest: XYU (anything that is unreliable). No probative power.