Fast forward to the 21st Century. Empowered by the modern days’ neuroscience, neuropsychology, Behavioral Economics, fMRI Machine, Social Sciences, Mathematics, Physics, Medical Science, and more, and applying critical thinking, now we have a little better understanding of how the human brain and mind works. David Eagleman described in a great detail how our brain works in his bestselling book The Brain: The Story of You.
Human brain has about 86 billion neurons. Our brain functionally can be modeled into 3 distinct categories: System 1, System 2 and Autonomic Nervous System (ANS). System 1 and System 2 are sometimes referred to by Type 1 and 2. System 1 and ANS combined is about 84% of our brain, whereas System 2, frontal cortex, is only 16% of our brain. ANS resides just below System 1. Our gut and spinal cord have 100 million and 70 million nerve cells respectively. Our heart has only 40,000 nerve cells. Nobel Laureate Daniel Kahneman and Amos Tversky in partnership first discovered System 1 and 2, the most important aspects of our brain in terms of how our thought arises.
The ANS was first evolved over 800 million to a couple of billion years ago. ANS is responsible for signaling and operating all bodily functions such as heart rate, body temperature, blood pressure, kidney function, thyroid gland, etc. Endocrine system is part of ANS.
System 1 is the result of hundreds of millions of years of evolution. This is our subconscious mind. We are not consciously aware of the processing that takes place in System 1 or in the autonomic nervous system. System 1 is far more compact than System 2. System 1 is several hundred times faster than System 2. Our emotion, love, hate, anger, instincts, sensations, feelings, compassion, empathy, resides in System 1. Various parts of System 1 can operate in parallel.
Whereas System 2 is mostly our frontal cortex, this includes neo cortex. System 2 is a relatively very recent development, of the past couple of hundred thousand years of homo-sapient evolution. System 2 is slow, cognitive, deliberate, serial processing, uses reason, logic, etc. System 1 and 2 work together and have some feedback mechanism to influence each other. For example, with meditation, Wim Hof Method, with proper practice one can influence System 1 and even the autonomic system (ANS) to a limited extent. Similarly, System 2 rational, logic processing can be sped up with the right kind and amount of passion. Passion originates in System 1.
Nobel Laureate in Economic Sciences, Daniel Kahneman, in his bestselling book Thinking, Fast and Slow (2011) explained how System 1 and 2 works.
Although we need both, System 1 and 2, but to rapidly and effortlessly function in autonomous mode, using habit rather than deliberate action, we need System 1 more than System 2. Self-mastery, quitting age old bad habits and acquiring new good habits over time are formed in System 1. Charles Duhigg explains the power of habit in his bestselling book The Power of Habit.