“Without being able to explain it to myself well,” returned Emile, “I see that it is so. We move and we think we see the other things moving. The faster we go, the faster the other things seem to go.”
“You hardly suspect, my little friends, that Emile’s naïve observation leads us straight to one of the truths that science has had the most trouble in getting accepted, not on account of its difficulty, but because of an illusion that has always deceived most people.
“If men passed their whole life on a railroad, without ever getting out of the car, stopping, or changing speed, they would firmly believe trees and houses to be in motion. Except by profound reflection, of which not everybody is capable, how could it be otherwise, since none would have seen the testimony of their eyes contradicted by experience? Of those that have been convinced, one sharper than the others rises and says this: ‘You imagine that the mountains and houses move while you remain at rest. Well, it is just the opposite: we move and the mountains, houses, and trees stand still.’ Do you think many would agree with him? Why! they would laugh at him, for each one sees, with his own eyes, mountains running, houses traveling. I tell you, my children, they would laugh at him.”
“But, Uncle—” began Claire.
“There is no but. It has been done. They have done worse than laugh; they have become red with anger. You would have been the first to laugh, my girl.”
“I should laugh at somebody asserting that the car moves and not the houses and mountains?”
“Yes, for an error that accompanies us all through life and that every one shares, is not so easily removed from the mind.”
“It is impossible!”
“It is so possible that you yourself, at every turn, make the mountain move and the car that carries us stand still.”
“I do not understand.”