Fast and slow thinking
This section contains exercises that can be used to warm-up participants at the beginning of critical thinking sessions or to visually demonstrate the operation of the two thinking systems (see below).
This section is based on the ideas of American psychologist, cognitive scientist, and Nobel laureate in Economics, Daniel Kahneman. In his book "Thinking, Fast and Slow," Kahneman (2011) introduces the idea of two thinking systems:
“In the story I will tell, Systems 1 and 2 are both active whenever we are awake. System 1 runs automatically and System 2 is normally in a comfortable low-effort mode, in which only a fraction of its capacity is engaged. System 1 continuously generates suggestions for System 2: impressions, intuitions, intentions, and feelings. If endorsed by System 2, impressions and intuitions turn into beliefs, and impulses turn into voluntary actions. When all goes smoothly, which is most of the time, System 2 adopts the suggestions of System 1 with little or no modification. You generally believe your impressions and act on your
desires, and that is fine—usually. When System 1 runs into difficulty, it calls on System 2 to support more detailed and specific processing that may solve the problem of the moment. System 2 is mobilized when a question arises for which System 1 does not offer an answer.”

Both systems are vital to our survival. System 1 helps conserve energy by allowing us to avoid prolonged thinking when it's unnecessary. We can never entirely shut off System 1. System 2 is responsible for conscious awareness and complex cognitive operations. Critical thinking is associated with System 2. Activating it requires effort and intention. However, some processes can eventually be transferred from System 2 to System 1, enabling us to spend less time on certain tasks.
Objective:
To allow participants to physically experience the shift from System 1 to System 2 thinking.
Number of participants:
5 to 25
Age range:
15+
Duration:
10 minutes
How to conduct:
The effect described below was first identified in a German study in 1929. Based on it, psychologist John Stroop conducted three experiments, which later became known as the Stroop tests.

Step 1:
Invite one volunteer from the group to read the words aloud, ignoring the color of the letters and focusing on the meaning of the words. Time how long it takes to complete the task.

Step 2:
Ask the same volunteer to name the colors of the words. For instance, when seeing the word "black" written in green letters, the volunteer should say "green." Time how long it takes this time.

Ask the volunteer to describe what they felt during the first and second steps. Then ask to imagine what scenario a person might complete the second round as quickly as the first (for example, if the words are written in a foreign language whose meanings are unknown and thus do not distract the participant).

Note:
Usually, participants take twice as long in the second round because this is when System 2 is activated. The individual consciously forces themselves not to read the written words automatically but to think about their color, thus slowing down.
Objective:
To allow participants to experience the shift from System 1 to System 2 thinking.
Number of participants:
5 to 25
Age range:
12+
Duration:
10-15 minutes
How to conduct:
In the classic version of minute mysteries, the facilitator describes a confusing situation, and participants ask clarifying questions to guess what happened. The questions should be closed, meaning the answers can only be "yes," "no," or "irrelevant."
Minute mystery (read out loud twice):

John and Bill were in a room. John left the room. When he returned a while later, he saw that the window was open, a broken jar was on the floor, and Bill was dead next to it. How did Bill die?

Ask those who know the answer to raise their hands and offer to let them act as wise observers (if the game drags on, the group can turn to them for help and ask them to pose a crucial question).

Ask the remaining participants to ask closed questions.
After the puzzle is solved, ask the participants what was happening in their minds when they were asking questions that didn't advance the group toward the goal.

Solution

Note:
The group may ask between 5 and 15 questions before someone asks the key question: "Is Bill a human?" This short exercise demonstrates the operation of the two systems: questions asked automatically don't help us move toward the solution, and only thoughtful questions enable us to reach the goal. Additionally, this exercise shows how difficult it can be to start doubting the most obvious things. When we hear "John" and "Bill," we usually take it for granted that they are people – and go down a rabbit hole of typical detective puzzle questions. The power of critical thinking lies in asking questions about what seems obvious.

Important:
Minute mysteries serve as metaphors that demonstrate the power and complexity of critical thinking. Not every minute mystery is suitable for demonstrating the operation of the two thinking systems.
Bill was a fish living in the jar. When John left the room, a draft opened the window, the jar fell, leaving Bill without water.
Objective:
To allow participants to experience the shift from System 1 to System 2 thinking.
Number of participants:
1+
Age range:
12+
Duration:
10 minutes
How to conduct:
The exercise can be done either sitting or moving around.

Explain that the exercise will consist of three steps, each with its own instructions.

Step 1:
Ask participants to extend the index finger of their right hand if they are right-handed, or their left hand if they are left-handed. Give the following instruction: for 30 seconds, move around the room continuously, pointing at different objects and quickly naming each one out loud. Point and name, point and name. On your command, the group begins moving chaotically. After 30 seconds, say "Stop." You may ask the group, "How did you feel during this exercise?" In a large group, ask a few volunteers rather than everyone.
Step 2:
Explain that they will again move around the room for 30 seconds, pointing at objects and naming them, but with one difference: they must name the objects with a one-step delay. That is, when pointing at the first object, they don’t name it, but when pointing at the second object, they name the first one, and so on. After 30 seconds, say "Stop." Ask the participants, "How did you feel compared to the first exercise?" In a large group, ask a few volunteers rather than everyone.
Step 3:
In this step, participants will again point at objects but should name anything but the objects they are pointing at. There are no other restrictions. For example, pointing at a table, they might say "unicorn." After 30 seconds, say "Stop." Ask the participants two questions. The first question: "What objects did you name?" The second question: "During which exercise(s) do you think System 1 was working, and during which exercise(s), System 2?"

Note:
Observe the speed of participants' movements during each step. Typically, System 1 is active in the first step, with participants moving quickly and naming objects without delay. In the second step, movements slow down as it takes time to recall and name the previous object. Here, System 2 begins to work. The third step can vary: for some, System 2 activates as they creatively name different, often non-existent objects. However, participants might also take an easy route, naming items in a sequence like "apple, banana, pear...". Although they are formally completing the task by calling objects by other names (if apples and pears are not present in the room), System 1 might take over to conserve energy and suggest easy strategies.