When you read Meditations 3.15 there seems to be a message that the foolish neither understand the world they live in, nor the real meaning of what they say in  the words they use. It seems to contrast outward senses such as sight and smell with an inward vision. It means looking beyond the obvious. That vision can also be your own personal power. Personal power is not about control but more of a person's attitude or state of mind. Its primary aim is self-mastery. Your personal power is rooted in your ability to believe you can change your life and achieve your goals. Without this understanding, you will not have the motivation or confidence you need to work hard, overcome obstacles, and accomplish the many tasks that are required to become the best version of yourself. And none of that is possible without a growth mindset.