The issue or the ruling which is proved by another religious evidence, has its religious, logical, or natural concomitants. The questions is whether these concomitants are valid too? The common viewpoint is that the logical and natural concomitants of 'Ijtihādī evidences are valid, but not of practical principles. The present study investigates the arguments regarding this issue with descriptive-analytical method, using library sources. In contrary to the viewpoint of the majority of scholars, the author believes that the logical and natural concomitants (Muthbitāt) of practical principles are also valid.