Comment Rule 401 makes no distinction between relevancy and materiality. The concept of materiality is merged into the concept of relevancy and retains no independent viability.
Evidence is relevant if it is likely to affect the probability of a fact of consequence in the case.
If the evidence has any probative value at all, the rule favors its admission. Such has been the experience under Federal Rule of Evidence 401 which is identical to this rule. Young v. Illinois Cent. Evidence to prove a collateral fact is relevant if the collateral fact has a tendency to prove or disprove an issue in the case.