Omniscience is the capacity to know everything infinitely, or at least everything that can be known about life, the universe, thoughts, feelings, etc. In monotheism, this ability is typically attributed to God. This concept is included in the Qur'an, in which Allah is called "Al-'aleem" on multiple occasions. This is the infinite form of the verb "alama" which means to know.
There is a distinction between:
Some modern theologians argue that God's omniscience is inherent rather than total, and that God chooses to limit his omniscience in order to preserve the freewill and dignity of his creatures. Certain theologians of the sixteenth century, comfortable with the definition of God as being omniscient in the total sense, chose to rebuke created beings' ability to choose freely, and so embraced the doctrine of predestination.
Nontheism often claims that the very concept of omniscience is inherently contradictory.
Some theists argue that God created all knowledge and has ready access thereto. This statement invokes a circular time contradiction: presupposing the existence of God, before knowledge existed, there was no knowledge at all, which means that God was unable to possess knowledge prior to its creation. Alternately, if knowledge was not a "creation" but merely existed in God's mind for all time there would be no contradiction. In Thomistic thought, which holds God to exist outside of time due to his ability to perceive everything at once, everything that God knows in his mind already exists. Hence, God would know of nothing that was not in existence (or else it would exist), and God would also know everything that was in existence (or else it would not exist), and God would possess this knowledge of what did exist and what did not exist at any point in the history of time. In short, God's mind would be the equivalent of an inalterable textbook which would contain all knowledge of everything in history within it, albeit an infinite one.
That some entity is omniscient in the sense of possessing all possible propositional knowledge does not imply that it also possesses all possible experiential knowledge.
Opinions differ as to whether the propositionally omniscient God of the theists is able to possess all experiential knowledge as well. But it seems at least obvious that a divine infinite being conceived of as necessary infinitely knowledgeable would also know how (e.g. a finite person [man] dying feels like as He [God] would have access to all knowledge including the obvious experiences of the dying human). There is a third type of knowledge: practical or procedural knowledge (knowing how to do). If omniscience is taken to be infinite then all knowledge of all types would be full known and comprehended.
A related but distinct ability is omnipotence (unlimited power). Omniscience is sometimes understood to also imply the capacity to know everything that will be.
Foreknowledge and its compatibility with free will has been a debated topic by theists and philosophers. Although free will is often used as a straw man as its importance is relatively minor in the theist’s books such as the Bible or the Qur'an. The argument that divine foreknowledge is not compatible with free will is known as theological fatalism. If man is truly free to choose between different alternatives, it is very difficult to understand how God could know in advance which way he will choose. Various responses have been proposed:
Omniscience is also studied in game theory, where it is not necessarily an advantageous quality if one's omniscience is a published fact. An example is the game of chicken: two people each drive a car towards the other. The first to swerve to avoid a collision loses. In such a game, the optimal outcome is to have your opponent swerve. The worst outcome is when nobody swerves. But if A knows that B is in fact omniscient, then A will simply decide to never swerve since A knows B will know A's logical decision and B will be forced to swerve to avoid a collision—this is assuming each player is logical and follows optimal strategy.
Omniscience is also used in the field of literary analysis and criticism, referring to the point of view of the narrator. An omniscient narrator is almost always a third-person narrator, capable of revealing insights into characters and settings that would not be otherwise apparent from the events of the story and which no single character could be aware of.
The concepts of omniscience can be defined naively as follows (using the notation of modal logic):
In words, for total omniscience:
For inherent omniscience one interprets Kxp in this and the following as x can know that p is true, so for inherent omniscience this proposition reads:
But a critical logical analysis shows that this definition is too naive to be proper, and so it must be qualified as follows:
The latter definition is necessary, because there are logically true but logically unknowable propositions such as "Nobody knows that this sentence is true":
If N is true, then nobody knows that N is true; and if N is false, then it is not the case that nobody knows that N is true, which means that somebody knows that N is true. And if somebody knows that N is true, then N is true; therefore, N is true in any case. But if N is true in any case, then it (= "Nobody knows that this sentence is true") is logically true and nobody knows it. What is more, the logically true N is not only not known to be true but also impossibly known to be true, for what is logically true is impossibly false. Sentence N is a logical counter-example to the unqualified definition of "omniscience," but it does not undermine the qualified one.
Unfortunately, there are further logical examples that seem to undermine even this restricted definition, such as the following one (called "The Strengthened Divine Liar"):
If B is true, then God (or any other person) does not believe that B is true and thus doesn't know that B is true. Therefore, if B is true, then there is a truth (viz. "B is true") which God doesn't know. And if B is not true (= false), then God falsely believes that B is true. But to believe the falsity that B is true is to believe the truth that B is not true. Therefore, if B is not true, then there is a truth (viz. "B is not true") which God doesn't know. So, in any case there is a truth that God does not and cannot know, for knowledge implies true belief.
While sentence N is a non-knower-relative unknowability, B is a knower-relative unknowability, which means that our concept of omniscience apparently needs to be redefined again:
All links retrieved December 20, 2018.
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