Caveat Notarius – Concepts: Consideration and cause
Art. 2439. Definition [of sale]. Sale is a contract whereby a person transfers ownership of a thing to another for a price in money. The thing, the price, and the consent of the parties are requirements for the perfection of a sale.
Art. 1906. Definition of contract. A contract is an agreement by two or more parties whereby obligations are created, modified, or extinguished.
Art. 1966. No obligation without cause. An obligation cannot exist without a lawful cause.
Art. 1967. Cause defined; detrimental reliance. Cause is the reason why a party obligates himself.