Obligation – a juridical necessity to give, to do, or not to do.
A juridical relation whereby a person (creditor) mat demand from another (debtor) the observance of a determinate conduct, and in case of breach may obtain satisfying from the assets of the latter.
Quasi-contracts- Those juridical relations arising from lawful, voluntary and unilateral acts, by virtue of which the parties become bound to each other based on the principle that no one shall be unjustly enriched or benefited at the expense of another.
Negotiorum gestio – arises whenever a person voluntarily takes charge of the agency or management of the business or property of another without any power or authority from the latter.
Solutio Indebiti – arise when a person unduly delivers a thing through mistake to another who has no right to demand it.
Quasi –delicts – An act or omission by a person (torteasor) which causes damage to another giving rise to an obligation to pay for the damage doner, there being fault or negligence but there is no pre-existing contractual relation between the parties (art 2176).
Negligence – failure to observe for the protection of the interest of another person, that degree of care, precaution and vigilance which the circumstances justly demand, whereby such other person suffers injury.
Determinate or specific – object is particularly designated or physically segregated from all other of the same class.
Generic – object is designated merely by its class or genus.
Limited generic thing – when the generic objects are confined to a particular class, e.g. an obligation to deliver one of my cars,
Jus ad rem – a right enforceable only against a definite person or group of persons.
Jus in re – a right enforceable against the whole world.
Default or Delay – Non- fulfillment of the obligation with respect to time.
Mora solviendi- delay of the debtor to perform his obligation.
Mora accipiendi- delay of the creditor to accept the delivery of the thing which is the object of the obligation.
Fraud – Deliberate and intentional evasion of the fulfillment of an obligation. Implies some kind of malice or dishonesty and it cannot cover cases of mistake and errors in judgment made is good faith.Diligence of Good Father of a Family – reasonable diligence which an ordinary prudent person would have done under the same circumstances.
Fortuitous event – an event which could not be foreseen or which though foreseen was inevitable.
Accion subrogatoria – to be subrogatred to all the rights and action of the debtor save those which are inherent in his person.
Accion paulina – impugn all the acts which the debtor may have done to defraud them.
Pure obligation – One whose effectivity is subrogated to the fulfillment or non-fulfillment of a condition or upon the expiration of a condition or upon the expiration of a term or period and is demandable at once.
Conditional obligation – one whose effectivity is subrogated to the fulfillment or non–fulfillment of a future and uncertain fact or event.