1. Natural Justice: This principle encompasses two key rules:
   • Audi Alteram Partem: The right to be heard.This means that no one should be condemned unheard.
   • Nemo Judex in Causa Sua: No one can be a judge in their own cause. This prevents bias and ensures impartiality.
2. Res Judicata: This principle states that once a matter has been finally decided by a competent court, it cannot be reopened or re-litigated.

Latin Maxims

• Ab Initio: From the beginning. This maxim is used to describe acts that are void from the start.
• Actio Personalis Moritur Cum Persona: A personal action dies with the person. This means that certain personal rights, like defamation, cannot be claimed by heirs.
• Actus Reus Non Facit Reum Nisi Mens Sit Rea: An act does not make a man guilty unless his mind is guilty. This principle emphasizes the importance of mens rea or guilty intent.
• Audi Alteram Partem: Hear the other side. This is a fundamental principle of natural justice.
• Caveat Emptor: Let the buyer beware. This maxim emphasizes the buyer’s responsibility to inspect goods before purchasing.
• Damnum Sine Injuria: Damage without injury.This means that harm without a legal wrong is not actionable.
• Delegatus Non Potest Delegare: A delegate cannot delegate. This principle prohibits delegation of authority.
• Ejusdem Generis: Of the same kind. This rule of interpretation is used to interpret general words following specific words.
• Expressio Unius Est Exclusio Alterius: The express mention of one thing excludes another. This rule is used to interpret statutes.
• Ignorantia Juris Non Excusat: Ignorance of the law is no excuse.
• Injuria Sine Damno: Injury without damage. This means that a legal wrong can be actionable even without actual damage.
• Nemo Judex in Causa Sua: No one can be a judge in his own cause. This is a fundamental principle of natural justice.
• Noscitur a Sociis: A word is known by the company it keeps. This rule of interpretation is used to interpret words in context.
• Res Ipsa Loquitur: The thing speaks for itself. This principle is applied in negligence cases where the mere occurrence of an accident suggests negligence.
• Salus Populi Suprema Lex: The welfare of the people is the supreme law.
• Ubi Jus Ibi Remedium: Where there is a right, there is a remedy.

Other Important Legal Concepts

• Estoppel: A legal principle that prevents a person from denying a fact that they have previously asserted.
• Res Judicata: A matter already judged. Once a court has made a final decision, it cannot be reopened.
• Limitation Period: The time within which a legal action must be commenced.
• Bona Fide: In good faith.
• Mala Fide: In bad faith.