People observe perceived reality through the senses. This reality is constrained by the senses. For example, the human eye can only perceive certain wavelengths of light. So perceived reality is fundamentally uncertain. There is no guarantee that it is an exact representation of reality. People also observe unperceived reality. For example, people observe the atom even though is not perceivable through the senses. Some people observe unperceived reality purely through reason. For example, a person can observe the nature of the universe just by rationally thinking about it. Some people observe unperceived reality through perception and reason. For example, scientists observe the atom using perception and reason. They use perception to observe results of experiments. Then they use reason to use these results to observe the atom. Similarly religious people observe god using perception and reason. They use perception to observe life events. Then they use reason to use these life events to observe god. But all observations of unperceived reality are uncertain. While perceived reality is uncertain due to uncertainty in perception, unperceived reality is uncertain due to uncertainty in perception and uncertainty in reason.