Hume pointed out that we usually assume that we are the same as we were five years ago, even though we have changed in many ways, we appear to be the same as we were five years ago. personal. We will also think about how much time can change a person's inner self without changing the person himself. But Hume denied that there was any distinction between the mysterious self and the various personalities that a person carries. When we start to introspect ourselves, we will find: "We can never have any consciousness unless we rely on a specific feeling; human beings are just a collection or a package accumulated by many different feelings, which are always in the same place." They alternate with each other in an unimaginably fast flow. "He pioneered modern agnosticism, being skeptical of any existence beyond perception, and holding a negative attitude towards the objective regularity and causal inevitability of the external world. He believed that perceptual perception is the only object of knowledge, and perception can be divided into two categories: impression and concept. However, he believed that people could not go beyond perception to solve the problem of the source of perception. Denies the objectivity of causal connection and believes that causal connection is only a concept formed due to the sequence of impressions. In terms of ethics, he advocates utilitarianism and believes that happiness and interests are consistent. He also used his empiricism, skepticism and utilitarian ethics to discuss issues related to the concept of God and religion.