Martha Michling (plaintiff) and others brought suit against her deceased husband’s employer, the Truck Insurance Exchange (defendant), to recover benefits provided by the Texas Workman’s Compensation Act. At trial, Martha testified that her husband, Hugo, had left for work in good health one day, but arrived home earlier than usual. She stated that as he exited his car, Hugo stumbled and said that his head was hurting him terribly. Martha testified that Hugo indicated that the bulldozer he operated at work slipped off a hill and he hit his head on an iron bar. Hugo later died at a hospital. There was no other testimony to corroborate Martha’s statement that Hugo had been injured at work. A physician testified that Hugo died from a cerebral hemorrhage resulting from a congenital weakness in one of the blood vessels in his brain that may have been caused by a cough, strain, a blow to the head, or may have occurred spontaneously. The jury found in favor of Michling and Truck Insurance Exchange appealed. The court of civil appeals affirmed the trial court’s judgment. The Texas Supreme Court granted certiorari to review.