Beyond the Dual Process Model - Welcome to the Tri-system!

The Tri-System - Bold new world or fast track to disaster?

Beyond the Dual Process Model

IB Psychology students are usually familiar with the idea of the Dual Process Model of thinking and decision making. First described in terms of 'System 1' and 'System 2' by Stanovich and West (2000) and then made famous by Malcolm Gladwell (Blink) and Daniel Kahneman (Thinking, Fast and Slow), this simple model seems to have good predictive power. Evidence for cognitive biases (the tell tale signs of system 1) is overwhelming, (although one or two biases may have fallen foul of the replication crisis) while it seems clear that we are able to think more slowly at times, comparing possible solutions and considering the pros and cons of each one. However, new research suggests it may be time to go beyond the dual process model and find out if three really is the magic number.

Welcome to the Tri-system

Now we have the suggestion that there is a third system of thinking - artificial cognition. Psychologists Steven Shaw and Gideon Nave have argued that we are using AI as an alternative way to make decisions - that we are not using system 1 or system 2, but delegating decision making to our digital database of choice. This new 'system' is fast but also compares multiple possibilities, leading to a sense that this is the best of both worlds (fast and effortless like system 1, thorough like system 2). Not surprisingly, we seem to have a very high sense of certitude for decisions made using this system.

Of course, this may not be wise. The assumption that AI has considered all possibilities in a rational, balanced and fair way can very quickly start to feel like a system 1 kind of situation. After all, when AI confidently gives us the 'best itinerary for an island-hopping adventure in Greece', what has it really done to arrive at this conclusion? What biases are built into the system? What are the ethical implications if we start to trust machines more than we trust other people? Where does this leave Human Development or Human Relationships?

It's all very worrying, especially for psychologists of a certain age. Maybe the first Terminator movie (and all of The Matrix movies and definitely Marvel's Avengers: Age of Ultron) should be required viewing in schools ...

Think about this ...

Could this be a good topic for an IA? How could you design an experiment to identify system 3 in operation?

HL Extension - How could this impact of technology connect to Learning and Cognition?

Further Reading

Gladwell, M. (2005). Blink: The power of thinking without thinking. Little, Brown and Company.

Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux.

Shaw, Steven D and Nave, Gideon, Thinking—Fast, Slow, and Artificial: How AI is Reshaping Human Reasoning and the Rise of Cognitive Surrender (January 11, 2026). http://dx.doi.org/10.2139/ssrn.6097646

Stanovich, K. E., & West, R. F. (2000). Individual Differences in Reasoning: Implications for the Rationality Debate? Behavioral and Brain Sciences, 23, 645-665.

https://doi.org/10.1017/S0140525X00003435

Sutton, J. (2016, June 7). What crisis? What reproducibility crisis? The Psychologist. British Psychological Society. https://www.bps.org.uk/psychologist/what-crisis-reproducibility-crisis