Witness credibility impaired by witness inclination to speculate

The Court is deeply disturbed by Tans apparent propensity to assume and speculate on vital facts. Courts, we reiterate, are not permitted to render judgments upon guesses or surmises. Suspicion, it has been said, cannot give probative force to testimony which in itself is insufficient to establish or to justify an inference of a particular fact. The sea of suspicion has no shore, and the court that embarks upon it is without rudder or compass. [G.R. No. 119722. December 2, 1996]