The day has special significance for America's nearly 30 million nonreligious people. In humanist community, Feb. 12 is "Darwin Day."

"Darwin has become an all-purpose icon for humanists, who champion reason and science while rejecting superstition and dogma," said Matt Cherry, executive director of Institute for Humanist Studies in Albany, N.Y. "Darwin is definitive rebuff to fundamentalism."

In 2004, a Gallup poll found that only one-third of Americans believe Darwin's 19th century theory of evolution is a credible scientific theory. The same poll found that 45 percent of Americans believe God created humans in their present form roughly 10,000 years ago.

Massimo Pigliucci, Ph.D., a professor of evolutionary biology at SUNY-Stony Brook and author of Web column "Rationally Speaking", is shocked by how few Americans have a basic understanding of evolutionary biology and nature of science in general.

"If people had a better understanding of both we wouldn't be embarrassed in front of rest of world by cases such as one currently going on in Dover, Pa., where administrators are walking around local classrooms talking about 'intelligent design' and other nonsense," he said.

2. I, as a subject, am at centre of investigation : I should not accept something because someone else (of whatever kind and abilities) believes in it. I’ve to be satisfied with idea. However, I would accept something for practical convenience (e.g. As I believe in quantum phenomena though I’ve never experienced them in person.)

3. I feel therefore I am : The most certain belief in my own existence because I feel something at moment. It’s supposed to be 99.99...% certain (and not 100% because of principle of universal doubt). It’s supposed to be more certain than law of syllogism (if p implies q and q implies r then p implies r). Probability is supposed to be a byproduct of (human) ignorance.