Bragg once compared science to a coral reef, pointing out how the living organisms at the surface produce the growth of the reef on top of tens of hundreds of feet of skeletons of organisms that have long since died. The life of the reef is only at its surface; the life of science is only at its frontier. The main idea of this analogy is that present science is not created out of thin air, but rather, was a product of many years of research and development. This idea in itself implies that there is progress in science. Scientific methodologies as well as science as an institution have been developed in such a way to allow for growth and improvement. Like the growth of the reef, is a process of building upon the foundation created by our ancestors.
It is a common misconception that science progresses when a correct theory replaces a wrong one. The process is better described as the replacement of a wrong theory with a less wrong theory. However, before even beginning to understand how this can happen, one must examine the criterion that is used to judge a correct theory from an incorrect one. Determining whether a theory is "true- or "false- is a never-ending process; that is, a theory can never be conclusively falsified or proven to be the absolutely true. A theory is usually accepted as valid when it is proven by numerous experimental tests and there is no other theory that explains the phenomena better. The more tests that back up the theory the more confidence is placed in its truth. However, one can never be certain that there will not come a time in the future where a test will show that the theory does not apply in all cases. Newton's laws of motion, for example, were proved by every possible experiment for almost 250 years. The confidence in the theory was so high that it was hard to imagine that it was not the absolute truth. In the late nineteenth century, however, experiments on small objects and fast moving bodies showed that Newton's laws did not always apply.
