If you have a simple mind, your life will be peaceful. You will enjoy every moment of life. What is simple mind? A simple mind is basically, a peaceful mind. It is a mind that is at ease with everything. If you have that kind of mind, everything goes for you. If you have to eat food that is sour, you are okay with it. If you have to eat bitter food, you are okay with it. If people insult or praise you, it is the same to you.
It is a mind that does not discriminate. We live in a world where people discriminate. Most common discrimination we know are between races, ethnicity, gender etc. But at the most basic level of it, our 6 senses discriminate all the time. When we see things, we have a preference for color, size, shape. We don't like how this looks, how that looks. This smells good, that smells terrible. I don't like you, I hate you, I like you, I prefer him or her. This is mine, that is yours. I want this, I don't want that. Don't say that I am doing more work, and become arrogant; look down on people who are earning less money. We make discriminations all the time! How can our minds be peaceful when we are discriminating all the time?
So we have to have a non-discriminating mind. A non-discriminating mind is a simple mind, a peaceful mind. It is a mind of wisdom. Wisdom of what? Wisdom of understanding everything is fundamentally empty. By fundamentally empty, it means that things change all the time. If it is not empty, it stays there and never changes. Therefore, the wisdom of understanding emptiness brings about a peaceful mind. Understand that these discriminations arise because of attachments, and understand that if it can arise, then it can cease. If we are patient to contemplate on this, there is nothing to hold on to inherently! We are not affected by external states. We will be like the still water in the lake, that sees everything. You can see how deep the water is, the reflection of everything it sees.
With a simple mind, comes a peaceful life. A life that is contented right now. A life that is not turned by external states. You have your own life to live; you don't compare with others. You are at peace if you are poor or rich. You are at ease if you don't eat luxurious food. Thus, a peaceful life is a peaceful mind. A peaceful mind is a simple mind. A simple mind is a non-discriminating mind. A non-discriminating mind is a mind that does not attached, a mind of wisdom.