Thinking Fast and Slow How Your Brain Thinks

Chapter 4 explains these concepts. We associate ideas with each other based on their properties, categories, and the effects they have on each other. Priming involves impacting subsequent behavior in an unconscious manner by exposing a person to words, ideas, or visuals. Daniel offers experimental data to explain this phenomenon. System 2 thinks it’s in charge, but that is not usually the case.

Kahneman introduces the concept of cognitive ease where conditions are such that System 1 can take care of business. The opposite is cognitive strain where System 2 gets called into action. Strain happens when you are in a bad mood and when things don’t feel familiar. This is why cautious reactions to novel stimuli have survival value. If you want to be persuasive, appeal to System 1 by keeping things simple, clear, and easy to read. If System 2 gets in the game, the extra analysis will produce better results. Cognitive ease with System 1 fully in charge is both a cause and a consequence of a pleasant feeling.

The main function of System 1 is to maintain and update a model of your normal personal world. This model is constructed by associations that link circumstances, events, actions, and outcomes that occur regularly. System 1 detects violations of normality (surprises) with astonishing speed and subtlety. It also offers quick impressions of causality based on experience and can do so inappropriately in situations that require statistical reasoning.
Daniel discusses the halo effect, which deals with how first impressions shape how we judge people. The sequence in which we observe characteristics is often determined by chance but sequence matters. People also seek data that are likely to be compatible with their beliefs and first impressions. Jumping to conclusions is efficient System 1 behavior. Uncertainty and doubt are the domain of System 2. This also helps explain how framing effects impact judgment.

Chapter 8. System 1 continuously generates assessments of various aspects of a situation without specific intention and with little or no effort. This has survival value. If your eyes are open, System 1 computes a 3D representation of your field of vision.
Chapter 9. If a satisfactory answer is not found quickly to a hard question, System 1 may find a related question that it can quickly answer. It’s then up to System 2 to endorse the answer or put in the effort to check it out. For example, when asked if you are happy overall you may base your answer on your current mood.