It has often been said that we humans are guided by our hearts and our brains, emotions and thoughts or reasoning. That is a two-part image but it seems to me that it may work better to think of ourselves as having three sections of governance: emotions, conscious reasoning minds and unconscious minds. Such a scheme is in line with the book titled "Thinking: Fast and Slow" by Daniel Kahneman. In his book, fast thinking covers reflexes, habits and automatic responses, usually including what I say back to a friendly person who says "Hi". Slower actions including more conscious thinking, such as recognizing that the friendly person is that new German student and thinking to say "Guten morgan".
The books and authors listed here wrote about the parts of our minds that are governing, controlling and adjusting us all the time, without conscious effort on our parts.
https://sites.google.com/site/kirbyvariety/books-about-the-unconscious?pli=1
Physical things such as standing, walking and breathing, even sitting up at a desk or eating at a table, require many processes and abilities that we don't think about but still work without conscious thought. The book listed on the page above in red at the top does a memorable job explaining the conscious mind as a small part of our very complex brains. It is like a CEO who is only informed about issues that are controversial or difficult to handle.
One of the most interesting parts of our minds is our use of language. If I am explaining which way I plan to drive to town, the words I need to say come to mind in a rather fast stream. My lips and tongue manage to get the right English out without much trouble, quite different from what happens if I try to explain my driving plan to that German student's parents, me being without much German at all.
Histories of thought often focus on Rene Descartes (1596-1650). He was clearly a genius but even geniuses are influenced by the state of knowledge and culture in their time. Descartes was trying to think about the human mind and at the same time, trying to stay true to his religion and also avoid being in trouble with the ecclesiastical authorities. He famously said that we humans have mind and we have body and they are rather distinct. Modern thinkers and scientists have tons of questions and modifications of that position.
It is very clear that our whole bodies communicate with all parts of ourselves and that we have drives, urges, emotions and rapid decisions and impulses, despite our ability to sit with each other or a counselor and discuss in detail why we drink too much booze or how we lost 20 lbs. of fat. We are far more complex and are designed by nature (or God, if you wish) to be and do and feel much more than we can understand. Science and reason and experience are always trying for a more complete grasp of what we do and how and why, but we have a very long way to go.
