The question of why do so many humans believe in a god, in spite of no evidence in support of a god, has been a question that is begging for a evidenced-based answer. Below is my clear and concise answer to the question.
There are three inclinations of humans instilled through evolution that seem to be associated with belief in a god:
animals, including humans, to presume the purposeful intervention of a sentient or intelligent agent in situations that may or may not involve one. When this inclination extends to supernatural entities (gods, spirits, etc), some have used the term Hyperactive Agency Detection.
This article shows that life sprang from disorder not purpose. This article shows that evolution has no direction.
beliefs, intents, desires, pretending, knowledge,
etc.—to oneself and others and to understand that others have beliefs,
desires, intentions, and perspectives that are different from one's own. This link supports the contention that facility with theory of mind plays an important role in human
religiosity. Diminished theory of mind capacities correlate strongly
with low levels of religiosity.
** PLEASE NOTE: This does not explain organized religion. For that, this link not only expands on the above concepts, but also is a good introduction to how organized religion comes from our social evolution.
SCIENCE (from the Latin for 'knowledge') informs wisdom, reason and humanism. This is a 4-legged worldview within reality that maximizes well-being for individuals and society.