Did the sun rise this morning? Think carefully about the wording of the question. I did not ask whether it appeared to rise or whether you perceived it as rising. Indeed, what takes place in our perceptions and what occurs in reality do not always coincide. If you are at a stoplight facing frontward and in your peripheral vision you sense the car next to you moving forward, you may for a moment feel as though you are moving backward. That is, to your perception, you are moving backward; in reality, you are not. In reality, the earth rotates around the sun; in our perceptions, the sun appears to rise, transverse the sky, and set. One way philosophers distinguish between reality as it is and reality as we experience it is with the terms “objective” and “subjective.” Objectively, the sun did not rise this morning. Subjectively, it did.

At least since the time of Socrates, philosophers have disagreed as to whether there exists an objective reality beyond the subjective perceptions of various individuals or communities. On the one hand, the objectivist would say that for however many thousands of years human beings believed the sun to be actually rising, crossing the sky, and setting, before Copernicus set everyone straight; this error in the perception of prescientific peoples simply had nothing to do with the objective reality of what was really occurring. Everyone was equally mistaken. If, at some point in the future, all scientific knowledge is lost and human beings invent a myth that the sun is pulled across the sky every day by an invisible unicorn, even if everyone in the whole world subscribes to this belief, it will not change the objective reality one bit.