Every brain thinks differently. The cognitive functions discuss how we think.
Carl Jung was the first to discuss how the human mind processes information. He said that some of our thoughts were best described as rational, and some as irrational.
The rational functions were of a feeling or thinking nature. A person who valued feeling or thinking highly would be more conscientious and would think more about how they solved problems, what was right and wrong, and what was smart or rational.
Examples: Introverted and Extraverted Feeling. Introverted and Extraverted Thinking.
The irrational functions are of a perceiving nature. When we use them, we become more open-minded. We entertain new ideas and possibilities, or we look at and consider information, even if we might disagree with it, or think it to be unethical or wrong.
Examples: Introverted and Extraverted Intuition. Introverted and Extraverted Sensing.
Jung also stated that four of the functions he conceptualised were introverted or extraverted. Introverted functions were oriented by the inner world, intentions, mechanics, laws, history, and untested theory. Extraverted functions were oriented by the outer world, character, action, behaviour, and results.
The extraverted functions would consider what was happening around them and information they derived from studying their surroundings. By listening to someone, reading something, or investigating their environment, they would get information about what was right and wrong and what was happening.
Examples: Extraverted Thinking, Feeling, Sensing and Intuition.
The introverted functions were rather interested in intention, reason, motive, and what caused action. They would look into past information and past values and compare it to present information. They would theorise or philosophise on what they had experienced, or think about how and why something happened.
Examples: Introverted Thinking, Feeling, Sensing and Intuition.
The Sensing Functions
Introverted Sensing (IS)
Introverted sensing is used to consider past information, history, and rote data and knowledge about a situation, details about what has happened or what you know. It's an useful cognitive function for instructors and experts.
Extraverted Sensing (ES)
Extraverted Sensing is used to respond to what is happening around you and to share information about things that you see, hear, and feel in the moment. People with these functions tend to be good at navigating their surroundings and showing other people the right way forward.
The Intuitive Functions
Introverted Intuition (IN)
Introverted intuition is used to form theories and abstract ideas and images to explain your environment, your life, and your experience. People with this cognitive function tend to make great philosophers!
Extraverted Intuition (EN)
An extraverted intuitive will most likely be a great detective and investigator. They're good at considering new patterns and opportunities and putting two and two together.
The Thinking Functions consider how things work, what works, and what is rational based on evidence.
Introverted Thinking (IT)
This function is good for thinking about what you hear and see and how things work. It gives you information about what makes sense and what does not make sense based on your ability to rationalise and evaluate a situation rationally.
Extraverted Thinking (ET)
An extraverted thinking type is a pragmatic. They pay attention to what works, what gives the best results, and what seems to be the most effective way to get the job done. They're very good at thinking on their feet.
The Feeling Functions
Introverted Feeling (IF)
When you use introverted feeling, you consider the purpose, intention, or reason behind an action. Was there something behind what someone said or what made a person do what they did? Why did the lamp suddenly go on without anybody touching it? Ooh. Spooky.
Extraverted Feeling (EF)
Extraverted feeling is used to consider what you like and dislike in your environment. What do you find to be good and bad? What is good character and what is bad character? What is appropriate to say or do in a situation? Do you think that person is kind or rude?
I made this old infographic a while ago. Leaving it here for people who still like it!