The standard of proof in a civil case is the well-known preponderance (balance) of probabilities. This requires of the party on whom the onus lies, in order to be successful, to satisfy the court that he is entitled to succeed on his claim or defence, as the case may be (Pillay v Krishna 1946 AD 946 952-953). The onus of establishing a case in accordance with this standard is on the party who makes the assertion since if a person claims something from another in a court of law, he has to satisfy the court that he is entitled to it (Pillay v Krishna supra 951; and Van Wyk v Lewis 1924 AD 438 444). According to Voet (22.3.10) the position is: “He who asserts, proves, and nothe who denies, since a denial of a fact cannot naturally be proved, provided that it is a fact that is denied and that the denial is absolute.” The person who makes the claim, and accordingly bears the onus of proof, is invariably the plaintiff. However, there are situations in which the defendant bears the onus. This ordinarily happens when the defendant is not content with a mere denial of the claim against him but sets up a special defence. In respect of the special defence the defendant becomes the claimant. For the specialdefence to succeed the defendant must satisfy the court that he is entitled to succeed on it (Pillay v Krishna supra 952; Corpus Juris (D.44.1.1); and Voet 22.3.9).The word “onus”, in this context, refers to the duty which is cast on the particular litigant, in order to be successful, of finally satisfying the court that he is entitled to succeed on his claim or defence, as the case may be. This is the meaning of the word in its true and original (primary) sense. In this sense the onus never shifts from the party upon which it originally rested (South Cape Corporation (Pty) Ltd v Engineering Management Services (Pty) Ltd 1977 3 SA 534 (A) 548A-B). In a secondary sense the word means the duty cast upon a litigant to adduce evidence in order to combat a prima facie case made by the opponent. In this sense the onus refers to the burden of adducing evidence in rebuttal. This may shift or be transferred in the course of the case, depending upon the measure of proof furnished by the one party or the other (South Cape Corporation (Pty) Ltd v Engineering Management Services (Pty) Ltd supra 548).