The comedian Lily Tomlin said that reality is a crutch for people who can't handle drugs. Some philosophers also have a low opinion of reality, seeing it as a mere construction of people's minds or social contexts. In contrast, this chapter argues that the things investigated by science exist independently of our minds, construed as brains. Using perception and inference, brains can develop objective knowledge of reality, including knowledge relevant to assessing the meaning of life.
The previous chapter's conclusion that minds are brains has major implications for two central philosophical questions: what is reality, and how do we know it? These questions are interrelated, as consideration of what things exist needs to fit with discussion of what it takes to gain knowledge
about those things. For example, an empiricist who believes that knowledge can come only through the senses might conclude that physical objects such as lions and mountains are not real, because we sense only features of them, not the things themselves. At the other extreme, an idealist who believes that reality is inherently mental might also conclude that lions and mountains cannot be said to be real apart from how we think about them.