II. Why creationism and intelligent design are actively anti-scientific.

To understand the answer, it is important to understand how science works to generate understanding. These are rules that underlie all science, not just biology

We can summarize these rules:

• Science is logical.
• Science is naturalistic. It assumes the world can be explained completely in terms of energy, matter, space, time and their interactions -- nothing 'supernatural' needs to be added to explain the universe.
• Science is social. Based on experimental observations and logical arguments, unbiased observers who accept the 'rules of science' will eventually come to agree on the basic facts and their explanation.
• Uncertainty is easily identifiable. When multiple and competing 'answers' are in play, we can be certain that the 'question' remains unresolved.
• Science is progressive. Over time, more and more of the observable universe becomes explicable in scientific terms and our description of the world becomes increasingly accurate.

We recognize the progressive and experimentally-tested quality of well-established scientific ideas by giving them a special name, we refer to them as theories.

There are many theories in science, the Atomic theory, Quantum theory, the Big Bang theory, the Island Universe theory, Einstein's theories of relativity, the Cell theory and the theory of Evolution.

Each explains a large collection of observation, makes predictions and suggests new experiments.

Are theories true? Whether a theory is true or false is really two distinct questions. The more philosophical question is whether the theory is an prefect description of how the world actually is.

The second, more pragmatic question is whether, based on the theory, we can predict how the world will be observed to behave under specific circumstances.

Science can never know whether a theory is true or not, because we do not know for certain whether our experience of the world is accurate.

What we can know, and what our modern technical world is based on, is whether specific ideas work.

We can see the practical implications of the theory of evolution in the appearance of antibiotic resistance bacteria, and our own efforts to build new drugs. We see it in the presence of genetic variations that are beneficial in one environment and that can lead to debilitating disease in another.

Then why do scientists act as if their theories are true? For a very simple and a very human one. Theories are tested over and over, by many different people.

Because proving a well established theory is incorrect is a quick way to scientific 'stardom', there is a great pressure to find errors in established theories.

The longer a theory survives this type of detailed examination, the more certain we are that 'it works'. It is a natural, but not a logically rigorous conclusion, that it works because it is true.

For the scientist, however, what matters is that it works -- that it accurately explains the observable world. The we can use it to explain, understanding and manipulate our world.

When we understand the cause of a disease, we are on the way to cure it or prevent it.