This simple article describes the reasons for the lack of critical thinking skills. The 35% that won't wake up. And I will add one more to that list:Laziness.

Critical thinking skills are an important tool, especially when it comes to personal beliefs and academics. When applied, critical thinking is a powerful defense against ideas and opinions that are potentially harmful or blatantly wrong. Unfortunately, not everyone possesses this ability, although it can be taught. Understanding what suppresses critical thinking is an important step to obtaining a more open mind.

Indoctrination

Indoctrination is a major roadblock to critical thinking. When an individual is surrounded and constantly fed a one-sided view on things like personal beliefs or politics, it stifles critical thinking. Children and students are especially vulnerable to this, so critical thinking must always be encouraged. According to the Association of American Colleges & Universities, teaching students to be skeptical will "help them see through the distortions of propaganda, and enable them to assess judiciously the persuasiveness of powerful emotional appeals." (see source 1)

Lack of Intelligence

An article by the University of Phoenix, entitled "Can Critical Thinking be Taught in the Classroom?" asserts that a critical thinker "would need a level of intellectual and cognitive ability." The article implies that some people are more adept than others when it comes to being skeptical and analytical. This is understandable, because people who lack intelligence will find it much easier to simply accept certain ideas at face-value than take the time and effort to research them. According to the Media Awareness Network, "Critical thinking is about how to think, not what to think" and requires "curiosity, open-mindedness, skepticism, and persistence.' In other words, you cannot think critically if you are ignorant of its process. Critical thinking is not about assuming that everything you hear, read or see is potentially wrong. It is about taking any information provided and analyzing it using the critical thinking process. Without this understand, critical thinking skills will be nonexistent.

Arrogance

Your attitude can have a profound effect on critical thinking. Even if you are extremely intelligent, you will not think critically if you are not willing to venture outside your own opinions. According to the University of Phoenix, "What stifles critical thinking in some cases is an unwillingness to do research." In other words, if you are not humble, you will avoid examining alternate opinions for fear of being proven wrong.

Cognitive Impairment

According the Surgeon General, mental disability and mental illness can cause a variety of obstacles, including disturbances of thought and perception or cognitive dysfunction. As a result, individuals suffering from such issues may be at an intellectual disadvantage. Since critical thinking requires a certain degree of intelligence, cognitive impairment prevents people from grasping the complex rules and processes of critical thinking.

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