What is ideology in simple terms?
An ideology is a set of opinions or beliefs of a group or an individual. Very often ideology refers to a set of political beliefs or a set of ideas that characterize a particular culture. Capitalism, communism, socialism, and Marxism are ideologies.
– Vocabulary.com.
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Problem:
People can form a Belief or Belief System based on some facts, and the rest a set of opinions and beliefs that they and others have (that are not proven or even logical or common sense).
Its like lying to yourself that something is real, or that something or a situation exists and it doesn’t exist and is only real in your own mind.
Once a person is sure of their Beliefs they then push their beliefs on to other people, and this causes many to believe in something that is not actual fact and only a reality in a group of people’s minds.