In law and ethics, universal law or universal principle refers as concepts of legal legitimacy actions, whereby those principles and rules for governing human beings' conduct which are most universal in their acceptability, their applicability, translation, and philosophical basis, are therefore considered to be most legitimate. One type of Universal Law is the Law of Logic which prohibits logical contradictions known as sophistry. The Law of Logic is based upon the universal idea that logic is defined as that which is not illogical and that which is illogical is that which involves a logical contradiction, such as attempting to assert that an apple and no apple can exist at and in the same time and in the same place, and attempting to assert that A and not A can exist at and in the same time and in the same place.