The more we come to know, the more we realize how little we know. The more
we understand, the more clear it is that everything we have learned is nothing
compared to what we have yet to learn. Behind each locked door we have
managed to open are still more doors and more locks, and so on ad infinitum.
So science is not an arrival, but a journey. It is not a fixed body of knowledge or growing shelf of facts and theories, but an infinite series of questions. The most brilliant of scientists have been those who have sought not the right answers to give, but the right questions to ask.
And so we have progressed, not in a straight line, but from ignorance to
misconception, and from misconception to mistake, and from mistake to failure,
and from failure to insight, and from insight to discovery about ourselves and
our universe and how things work. It happened very slowly and haltingly at first and then faster and faster, picking up tempo until in the twentieth century it has reached a dizzying speed. In my own lifetime there have been revolutions in just about every branch of human knowledge. I wonder how many pages in my high school science books still stand. Today we laugh at how little we knew yesterday. Tomorrow we will laugh at how little we know today.
There are ordinary high school kids who can tell you now about strange
stars and invisible forces in the universe that even the brightest astronomer
knew nothing about only a few decades ago. Kids today know about an
expanding universe and the explosion that started it, the blast furnace of
creation, and When and How it most likely happened. They know, as our
grandfathers did not, that the continents are constantly on the move, fixed to
vast plates that slide over and bang against one another, rocking the earth. Kids today can tell you that more than 90% of the universe is so-called dark matter, invisible and unknowable. When I was a boy, radio still seemed a technological wonder and space exploration was something in the "Buck Rogers" comic strip. Today's children take television, computers, and cellular telephones for granted, as they do space stations and missions to Mars.