In his article, “What is it like to be a bat?” Thomas Nagel argues that there are facts about the conscious experience that are subjective and can only be known from that subjective perspective. Even if we know all the objective facts about bats, we may not actually know what it would really be like to be a bat. We might be able to imagine what it would be like to hang upside down, fly through the night, or use echolocation to track prey, but Nagel argues that we really couldn’t know what a bat’s experience is really like.

https://www.jstor.org/stable/2183914