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Q: What is “Common Knowledge in Game Theory?


A:  Much of what defines game theory is built around the accumulation, organization and application of knowledge. Knowledge is a familiarity, awareness or understanding of someone or something, such as factsinformationdescriptions, or skills, which is acquired through experience or education by perceiving , discovering  discovering, or learning.

Knowledge can refer to a theoretical or practical understanding of a subject. It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic.  Knowledge acquisition involves complex cognitive processes: perceptioncommunication, reasoning and intuition. One of the important concepts concerning knowledge and game theory in all its form is Mutual Knowledge. Mutual knowledge is a fundamental concept about information in game theory, logic, and the process of accumulating knowledge especially with regard to methods, validity, and scope of how this takes place (Epistemology) It is this  is the investigation that allows and enables us to distinguish justified belief from opinion.  An event is mutual knowledge if all the players know that the event occurred. However, mutual knowledge by itself implies nothing about what players know about other players’ knowledge: i.e. it is possible that an event is mutual knowledge but that each player is unaware that the other players know it has occurred. Common knowledge is a related but stronger notion; any event that is common knowledge is also mutual knowledge. This is the knowledge core to visionary thinking – the subject of one of my Ebooks at www.realUguru.com


Visionary Thinking: Tips, Techniques & Strategies by Lewis Harrison

   Common knowledge is knowledge that is known by everyone or nearly everyone, usually with reference to the community in which the term is used. Common knowledge need not concern one specific subject, e.g., science or history. Rather, common knowledge can be about a broad range of subjects, such as science, literature, history, and entertainment. Often, common knowledge does not need to be cited. Common knowledge is distinct from general knowledge. The latter has been defined by differential psychologists as referring to “culturally valued knowledge communicated by a range of non-specialist media”, and is considered an aspect of ability related to intelligence. Therefore, there are substantial individual differences in general knowledge as opposed to common knowledge.

The assertion that something is “common knowledge” is sometimes associated with the fallacy argumentum ad populum (Latin: “appeal to the people”). The fallacy essentially warns against assuming that just because everyone believes something is true, it is true. Misinformation is easily introduced into rumors by intermediate messengers.

In broader terms, common knowledge is used to refer to information that a reader would accept as valid, such as information that many users may know. As an example, this type of information may include the temperature in which water freezes or boils. To determine if information should be considered common knowledge, you can ask yourself who your audience is, are you able to assume they already have some familiarity with the topic, or will the information’s credibility come into question.


   Many techniques have been developed in response to the question of distinguishing truth from fact in matters that have become “common knowledge”. The scientific method is usually applied in cases involving phenomena associated with astronomy, mathematics, physics, and the general laws of nature. In legal settings, rules of evidence generally exclude hearsay (which may draw on “facts” someone believes to be “common knowledge”).

Conventional wisdom” is a similar term also referring to ostensibly pervasive knowledge or analysis.


Examples of common knowledge:

  • Parisis the capital of France.” Many capital cities of countries are considered common knowledge by most people.
  • “The Moon orbits the Earth.” Observation of the moon shows us that this happens. In addition,scientific findings give confirmation. At various periods in history, it was regarded as common knowledge that the Earth is flat and that the Sun orbits the Earth, although these theories were later found to be false.
  • “It is dangerous to mixammonia and bleach.” Though both common household chemicals, accidents involving the mixing of ammonia and bleach are rare, because the potentially lethal danger in their chemical reaction is a widely circulated cautionary tale.
  • “TheFifth Amendment to the United States Constitution grants American citizens the right to refuse to answer any question in a court of law that would endanger incriminating themselves.” “Pleading the Fifth” is a phrase commonly used in American colloquial speak, and even in such popular media as the sketch comedy series Chappelle’s Show. Thus it may be regarded as common knowledge in the United States.





A great basic book on information and knowledge can be purchased and downloaded by clicking below at:









You can purchase and download it at:



The RealUGuru’s Guide To Healing Your Emotions


Lewis Harrison is a writer, content-rich, motivational speaker, and an entrepreneur specializing in game based thinking, applied game theory and Game Thinking.


Known as the RealUGuru. He is the author of over twenty-two books published in five languages.  Including the business books.



Don’t forget to tune into my Radio show today at WIOX 91.3 FM or on your smart device at WIOXRadio.org.


If you are interested in business success in the 21st Century in the arts or in any other endeavor you need to read Lewis’ recently published business books.


You can find them here:




In addition Lewis is THE CREATOR OF Lewis Harrison’s Applied Game Theory,  seminar leader, futurist, NPR affiliated radio talk show (WIOXRadio.org) host, success and life coach and a best-selling author.

He is the creator of a web site – www.RealUGuru.com  that focuses on the application of gamification, decision science, positive psychology, happiness,  and visionary thinking to solve basic, complex and extreme problems. He is the creator of a free course on business success and human potential.

Here is a short interview with Lewis;




Lewis Harrison mentor, coach in the area Problem solving. Anexpert in Applied Game Theory. He is the founder and director of the Catskills Art and Culture Festival Based at the Catskills B & B in Stamford NY. https://thecatskillsbandb.wordpress.com

Learn more about his books at www.RealUGuru.com


His company www.eventschairmassage.com offers Corporate chair massage to meeting planners, event planners, association meetings and trade shows. He also offers these stress management and onsite massage services in NYC, Los Angeles, Las Vegas, Chicago, Dallas, Greensboro, Columbus Ohio and many other cities across the United States through www.NoStressSpeaker.com.



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