One of the most common types of anti-evolution argument is the
probability-based argument, and its greatest strength is the fact
that the average person does not know the concept of probability
very well, if at all. Creationists have many creative ways of
using public ignorance of probability to their advantage, but the
most common trick is to attack abiogenesis: the process by which
it is believed that the first self-replicating molecule was
produced in the primeval seas, billions of years ago.

Creationist arguments tend to rely on a common misconception:
to use a poker analogy, they assume that if you come up with a
very good hand, then you must be cheating. "But isn't
that true" you might ask? If someone comes up with a very
good hand in poker, doesn't that mean he cheated? Not
necessarily. It's possible, but you would need better
evidence than that.

In order to understand the flaws in the creationist probability
argument, one must first understand how you compute probabilities.
This should not be above the level of the average person because
they teach the basic concepts of probability in high-school algebra
class (or at least they did back when I went to school; I don't
know if the weakening of educational standards has rotted away this
part of the curriculum yet). The basic concept is disarmingly
simple: if the process is random, then you simply count the
total number of possibilities and then divide it by the number of
outcomes you're looking for. The execution, however,
can be quite complex and involves many potential pitfalls.

In the following pages, we will examine the concepts of
probability with several everyday examples, before looking at an
example of a typical creationist probability-based argument where
we can put these concepts to use.