The Teachings of Don Carlos
(My note: This passage of the book is translated by me from the original Czech version, so there might be some mistakes. The page may not match the original either).
Chapter VI., stop the inner dialogue, The key that opens the gate between worlds, page 148
“The ability to silence thoughts is one of the central themes of the knowledge systems that remain little known in the West.
The average person usually keeps thinking about something. I do not mean some focused thinking, just a simple act of uncontrolled thinking that we perform continuously. We constantly talk to ourselves in our thoughts. Don Juan calls it “internal dialogue” (IV – 18), and his interruption is one of the pivotal points of his teaching.
The fact that we constantly have a dialogue with ourselves in our minds is often considered a natural and inseparable human quality. It may even seem that you can stop thinking only after death, and that it is not possible to have a completely empty mind. Moreover, this belief confirms to us that if someone tries to stop their thoughts, they usually fail. This can only be achieved through specific methods that require systematic effort.
If we look at things from a broader historical and geographical point of view, humanity has always been interested in the ability to calm the mind. I would say that every human being longs for this art deep inside.
Castaneda even writes that in ancient times the art of inner silence was much closer to humanity. Gradually with the development and subsequent domination of rational thought (VIII – 125 to 127) completely seized individual experience (although for most people it was increasingly the less rational and the more mechanical).”