Dale Carnegie is one of my favorite authors and I find his books interesting because they provide a valuable insight to the life. This book is an international bestseller and is useful to be read in an early age so as to develop our thought process as we grow up with the ideas that this book has incorporated in us.
Some of the ideas given in the book are-
Speak ill of no man and speak all the good you know of everyone.
Say "Thank You".
If you know you’re wrong, admit it.
Friendliness begets friendliness.
Never neglect a kindness.
Start out by emphasizing areas of agreement.
Let the other person do most of the talking.
Let people come to your conclusions.
All of these are good but he has not advised honesty in his ideas. Sometimes his opinion goes like we should speak good of people so that they be think good of us but what if that guy is bad? This is the only flaw I found in the book.