Final answer:
Scholars from diverse fields offer explanations for why so many belief systems developed concurrently. They cite functional, economic, psychoanalytic, cognitive, and socio-cultural reasons, ranging from meeting human needs to cognitive predispositions, and from socio-economic benefits to the complexity of evolving religious thought and expansion.
Step-by-step explanation:
Different scholars offer a variety of explanations for the development of numerous belief systems within a single era. Some point to functional approaches, where religion is seen as addressing human needs, such as those detailed by anthropologist Bronislaw Malinowski. Karl Marx provided an economic perspective, famously denouncing religion as the 'opium of the people,' suggesting it pacifies the masses. Sigmund Freud, from a psychoanalytic standpoint, considered religion a fulfillment of childhood needs for security and forgiveness. Other theories suggest that the intrinsic nature of human cognition and the evolution-driven 'god engine' predisposes people to spiritual beliefs.
As belief systems expand, they may become burdened by inconsistencies and contradictions. Cultures or individuals engage in reflective thought, leading to the introduction of qualifiers and alternate interpretations to preserve the belief system. However, the process can become cumbersome, prompting scrutiny of fundamental beliefs and potentially leading to the adoption of new, more coherent belief systems.
Another angle considers the socio-cultural dynamics at play. For instance, the spread of religions like Christianity and Islam in Africa involved complex interactions including military conquest, commercial exchange, and cultural diffusion. People adopted these religions for various reasons, including the promise of an afterlife or tangible commercial benefits.