"Your glass will not do you half so much service as a serious reflection on your own minds"

This quote by Mary Astell motivates us to take a step back and review our own minds. It recommends that instead of relying on external sources such as a glass, we must focus on our own thoughts and sensations. This is since our own minds can provide us with more insight and understanding than any external source. By assessing our own minds, we can get a much better understanding of ourselves and our own thoughts and sensations. This can help us to make better decisions and lead a more fulfilling life. Astell's quote motivates us to take the time to review our own minds and to use this reflection to better ourselves.