Be vigilant...How to strengthen your brain abilities? It reaches a peak in intelligence, memory and

"Be vigilant"... two words that form a sentence, the purpose of which is advice, not command. The author Dale Carnegie is not accustomed to ordering his reader, but rather he is accustomed to having a friend sit with him, who gives him a summary of his experiences and expertise, and gives him advice, so he takes the two words as the main title of the book and then follows it. With a long and explanatory subtitle: "How to strengthen your brain capabilities? And reach the peak of intelligence, memory, and creativity."
Thus, the writer explains, starting from the title, why he asks the reader to be alert, and indirectly explains the goal that called him to write the book. Carnegie lived a fertile and wealthy life despite its difficulty. Therefore, he has a huge wealth of experience in many fields, and this is what allows him to be a mentor to people, and also gives his books and talks great credibility, as he does not speak in a vacuum or without experience and knowledge of what he is talking about.