System 1 could also be called a recognition. How do you recognize your house, or a friend? You do it subconsciously and automatically. System 1 is always on. Everytime you walk in a room, whether you want it or no, your body will immediately evaluate the situation – is it safe or not? You have no choice to “disable” it. Most of our interaction with environment and day to day routines are managed by this automatic, subconscious system. Other interesting aspect of system one is that it always brings only one solution, it is free from doubt. As soon as you decide between two or more options – it is a business of effortful logical system 2. Every time our automatic system 1 fails to recognize the situation – our logic, our system 1 is brought for help with also arsenal of logical decisions and options. System 2 is slow, it prefers to be lazy and use the least effort and the least amount of energy. First it tries to check of original system 1 intuition is correct, and if not, then it starts looking for other options or solutions.
How does it help with weight management? It makes a huge difference whether you ask yourself “how hungry am I” versus “how full am I”. You might find within yourself enough data to support either question, but if you ask yourself “how full” – as soon as you support it, you’ll stop looking for opposite and you will come to a reasonable “I am full”.