Thinking, Fast and Slow
The adage ‘you are what you eat’ is no doubt literally true, but when it comes to getting at the heart of what we are it is certainly more accurate to say ‘you are what you think’; for our identity emerges out of the life of the mind, and our decisions and actions (including what we eat) is determined by our thoughts. An exploration of how we think therefore cuts to the core of what we are, and offers a clear path to gaining a better understanding of ourselves and why we behave as we do. In addition, while many of us are fairly happy with how our mind works, few of us would say that we could not afford to improve here at least in some respects; and therefore, an exploration of how we think also promises to point the way towards fruitful self-improvement (which stands to help us both in our personal and professional lives). While thinking about thinking was traditionally a speculative practice (embarked upon by philosophers and economists) it has recently received a more empirical treatment through the disciplines of psychology and neuroscience. It is from the latter angle that the Nobel Prize winning psychologist Daniel Kahneman approaches the subject in his new book Thinking, Fast and Slow.
As the title would suggest, Kahneman breaks down thinking into 2 modes or systems. Slow thinking is the system that we normally think of as thought in the strictest sense. It is deliberate and conscious, and we naturally feel as though we are in control of it (Kahneman refers to it as system 2). System 2 is in play when we actively consider what we want to have for dinner tonight, or when we choose what stocks to buy, or when we perform a mathematical calculation. System 1, by contrast, is automatic and unconscious, and hums along continuously in the background. It constantly surveys the environment, and processes the incoming stimuli with razor speed.
System 1 is informed by natural drives and instincts but is also capable of learning, which it does by way of association (that is, connecting up novel stimuli with known stimuli according to shared characteristics, contiguity in time and place, or causality). The system is designed to give us an impression of our environment as quickly as possible, thus allowing us to respond to it immediately, which is especially important in times of danger. In order to do so, system 1 relies on general rules and guidelines (called heuristics). These heuristics are primarily geared to help us in the moment and are tilted towards protecting us from danger, and in this respect they are mostly very useful. Still, mistakes can be made, and the system was specifically designed to work in the environment in which we evolved, which is quite different from our current one, so this adds to its errors.
Over and above this, the impressions that system 1 forms are also fed up to system 2. Indeed, whenever system 1 senses something out of the ordinary or dangerous, system 2 is automatically mobilized to help out with the situation. And even when system 2 is not mobilized specifically out of danger, it is constantly being fed suggestions by system 1. Now, while the impressions of system 1 are fairly effective in protecting us from moment to moment, they are much less effective in long-term planning; and therefore, they are much more problematic here. Of course, system 2 is capable of overriding the impressions of system 1, and of avoiding the errors. However, as Kahneman points out, system 2 is often completely unaware that it is being influenced (and misled) by system 1; and therefore, is not naturally well-equipped to catch the errors. Much of the book is spent exploring the activities and biases of system 1, in order to make us more aware of how this system works and how it influences (and often misleads) system 2.
This is only half the battle, though, for while system 2 may be naturally poorly equipped to catch the errors of system 1, it is also often poorly equipped to correct these errors. Indeed, Kahneman argues that system 2 is simply not a paragon of rationality (as is often assumed in economics), and could stand to use a good deal of help in this regard. The most glaring deficiency of system 2, according to Kahneman, is that it is naturally very poor with probabilities and statistics. Fortunately, system 2 can be trained to improve here, and this is another major concern of the book.