What do we know about “the earth”?
Well, if you had asked that question to people in the 1400’s, they would have told you that they “knew” that the earth was the center of the universe. If you had asked Lord Kelvin, one of the greatest scientific minds of the 19th century, he would have told you that he “knew” that the earth was between 20 and 400 million years old. And if you had asked that question to most geologists in the early 20th century, they would have told you that they “knew” that the earth’s continents were fixed in place.
And of course, we now realize that what all these people “knew” about the earth was completely wrong.
On one level, the earth has been whatever the earth has been over its billions of years of history. But what has changed over just centuries is our understanding of what the earth is. In other words, the earth as an actual object in reality is different from the earth as we know it at any given moment.
Indeed, everything scientific — such as the earth, the sun, atoms, genes, the universe, or humanity — lives in these same two worlds: what it is in reality and what we understand about it right now.
Continue reading.
Follow us on
