Religion and Philosophy in the Third Space Age
Noncanon.
Transhumanist Philosophies
'Transhumanism' is the process of augmenting the basic human form. While medical devices like glasses and splints and even basic tools have been argued to be examples of 'augmentations', the term in practice refers to the various genetic, cybernetic and other major upgrades that became possible over the course of the 21st century.
Stauss-Kaserism
Contrary to popular perception in the Expanse, Stauss-Kaserism is technically a transhuman philosophy, except that it is hyper-incrementalist save for basic quality-of-life and medical alterations.
Tersiism
Dr. Tersi's philosophy advocates 'Genetic Meritocracy' - the establishment of a caste system where the rulers are transgenes with superior mental faculties, and exercise benevolent dictatorship. It predictably never gained wide traction, but sympathisers left on a number of longshots during the 2060s and 2070s, and remained prevalent in obscurity among several populations of the well-to-do such as those who founded the Kanon colony. Dr. Tersi unashamedly used monarchic imagery in his advocacy, a tendency reflected in surprisingly many of the governments based on his theories.
Post-physicalism
The posthumans were and remain the most radical and most successful transhumans, due to their approach of abandoning the flesh entirely for hyper-accelerated uploaded existence. The process has never caught on, however, due to the dangers of uploading and the rapid and severe alienation it causes among even most time-equalised 'mindstates'. To a baseline, uploading amounts to death and the afterlife, requiring severance from all worldly things. Even near death, many choose to remain close to those they care about.
Exhumanism
Christianity
Catholicism
Protestants
Orthodoxy
Minor and Extinct Sects
Reshanki Christianity
Reshanki Christianity holds that the End of Days is at hand and the Antichrist has appeared in the form of the Posthumans, who travelled back in time to prevent the rapture. It was founded on Corregidor during the early 2140s and never achieved a very large following, but the (extremely rich) founder's big-budget televangelism campaigns and public clashes with posthuman worshippers gave it a media presence above its weight. Mr. Reshanki retired to his ranch during the 2150s and has refused all interviews since, and the faith has no practicing worshippers remaining.
Islam
Sunni
Shia
Hinduism
Still trucking in India.
Buddhism
Minor Faiths and Philosophies
Church of the Immanent Eschaton
Minkowski Transcendentalism
Minkowski Transcendentalism advocates the abandonment of gravity and sin for holy spacebound life, so that the soul can be purified and escape the corrupt material world. It is localised almost exclusively to the Minkowski system, where it is the dominant and state religion. Primary injunctions warn against malice, greed and pride.
Unitary Solipism
Extinct Faiths and Philosophies
Kirnaism
Kirnaism preaches that all major prophets were posthumans who travelled back in time.