In Bridgman v. Safeway Stores, Inc., 53 Cal. 2d 443, 348 P.2d 696, 2 Cal. Rptr. 146 (Cal. 1960), the court stated that, "evidence that an inspection had not been made within a particular [period of] time prior to an accident may warrant an inference that the defective condition existed long enough so that a person exercising reasonable care would have discovered it." Id. at 698. Bridgman thus allows a plaintiff to prove the existence of constructive knowledge through inference, established by proof of insufficient inspections. Thus, "where . . . the owner operates his store on a self-service plan, . . . the exercise of ordinary care may require the owner to take greater precautions and make more frequent inspections than would otherwise be needed . . . . " Id. The requirement of actual or constructive knowledge on the part of the premises owner "is merely a means of applying the general rule stated above that the proprietor may be liable if he knew or by the exercise of reasonable care could have discovered the dangerous condition, and it does not alter the basic duty to use ordinary care under all the circumstances." Id.