I am standing on the threshold about to enter a room. It is a complicated
business. In the first place I must shove against an atmosphere pressing
with a force of fourteen pounds on every square inch of my body. I must make
sure of landing on a plank travelling at twenty miles a second round the
sun - a fraction of a second too early or too late, the plank would be miles
away. I must do this whilst hanging from a round planet head outward into
space, and with a wind of aether blowing at no one knows how many miles a
second through every interstice of my body. The plank has no solidity of
substance. To step on it is like stepping on a swarm of flies. Shall I not
slip through? No, if I make the venture one of the flies hits me and gives a
boost up again; I fall again and am knocked upwards by another fly; and so
on. I may hope that the net result will be that I remain about steady; but
if unfortunately I should slip through the floor or be boosted too violently
up to the ceiling, the occurrence would be, not a violation of the laws of
Nature, but a rare coincidence...
Verily, it is easier for a camel to pass through the eye of a needle than
for a scientific man to pass through a door. And whether the door be barn
door or church door it might be wiser that he should consent to be an
ordinary man and walk in rather than wait till all the difficulties involved
in a really scientific ingress are resolved.
Arthur Stanley Eddington, The Nature of the Physical World New York-
Cambridge, 1929, p. 342
