Ajivika is a deterministic philosophy that originated in ancient India during the 5th century BCE. It is based on the belief that all events and actions in the world are predetermined by fate and cannot be altered by human will or effort. The word "Ajivika" comes from the Sanskrit root "jiva" which means "living being" or "life force."

According to Ajivika philosophy, everything in the universe, including human beings, is governed by a cosmic force called "niyati," which translates to "destiny" or "fate." This force is believed to be beyond human control and is responsible for the cycle of birth, death, and rebirth. The Ajivikas also believed in the concept of karma, which states that one's actions in a previous life determine their fate in the current life.

The founder of Ajivika was Makkhali Gosala, who was a contemporary of the famous philosopher and teacher, Mahavira, the founder of Jainism. However, Ajivika philosophy did not gain as much popularity as Jainism or other major Indian religions such as Hinduism and Buddhism.

The Ajivikas believed in a strict code of conduct and followed a strict ascetic lifestyle. They believed that by renouncing worldly pleasures and desires, one could attain liberation from the cycle of birth and death. This liberation was known as "moksha" in Hinduism and "nirvana" in Buddhism.

One of the unique aspects of Ajivika philosophy was their belief in the concept of "ekantavada," which means "one-sidedness." This concept states that there is no absolute truth and that everything is relative and subjective. Therefore, the Ajivikas did not believe in the concept of a creator God or any form of worship.

The Ajivikas also had a strong belief in fatalism, which means that everything is predetermined and cannot be changed. This belief was often criticized by other Indian philosophies, such as Buddhism and Jainism, which emphasized the role of individual effort in attaining liberation.

In conclusion, Ajivika is a deterministic philosophy that emphasizes the role of fate and destiny in shaping human life. It was founded by Makkhali Gosala and was popular during the 5th century BCE in ancient India. Although it did not gain as much popularity as other major Indian religions, Ajivika philosophy had a significant influence on the development of Indian philosophical thought.