Many sophonts, both bioid and aioid alike, believe in the existence of a soul, a spiritual component of a thinking being, which may or may not be immortal according to creed. The development of uploading and mind-state copying caused many religions to consider the process by which one individual with a unique soul becomes two or more individuals, and whether or not the new individuals also have souls themselves. Many religions, such as the Etodists, believe that the soul is multiplied when an individual is copied, and the new soul(s) are equal in every respect to the old one. Others, such as the Soul-Divisionists, believe that the soul is divided and weakened by copying, a process which can only be healed by spiritual development over time. Another line is followed by the One Soul movement, proponents of which state that the act of copying does not produce a new soul at all.
The One Soul movement has been active in the Inner Sphere since the late First Federation Era. It has, at its base, the belief that a single sophont has a single soul that it is responsible for. This responsibility requires intelligent management and concern for the soul, lest it be dragged 'down' into a spiritual variant of a black hole by the weight of its deeds. Alternately, a 'light' soul could escape such drag, roving free and interacting with others rather than being captured eternally.
These sophonts are very much aware of and approving of IA (Intelligence Augmentation) adaptations to their 'born' capabilities, including uploading as it allows more attention to be spent on ethical ('light') behavior. Their belief structure is such that the 'Soul-bearer' 'primary' (original) sophont is considered to hold the single, irreducible soul regardless of how many copies are made, and thus other copies ('Soulless', in their terminology) have the responsibility of maintaining the 'Soul-bearer' in a state that the soul has an optimal chance of attaining freedom after death. It is not uncommon for large numbers of Soulless to die shortly after the loss of the Soul. The exact point of when the Soul is lost, however, is hotly disputed.
There are three subsects within the "one Soul" movement. These subsects are often at odds, sometimes violently, over these differences. Members of the first subsect, called "One Living Soul" believe that the Soul stays with the Soul-bearer until death. At that point, regardless of backups or other hi-tech resurrection capabilities employed, the Soul is gone and the whole group is Soulless, often with tragic consequences for the group in question.
Members of the second subsect call themselves "One Soul for Life", and believe that the life of the primary, maintained in whatever manner, is what maintains the Soul's presence. If the Soul-bearer dies permanently, the rest of the Soulless in the grouping tend to react violently against whatever caused the dissolution of the Soul-bearer, and then tend to die off in despondency.
The members of the final major subsect call themselves the "One Soul's Life", and maintain that the Soul is passed from the Soul-bearer to their next (based on chronological order of appearance) surviving copy. Obviously, this group is most interested in generating copies, to ensure the Soul a sufficient lifetime to generate 'lightness'.
In general, these various sects are willing to work together to prevent memetic contagion from 'Soul-bereft' or 'Soul-wasting' clades and groups that do not follow this set of teachings, even while maintaining their own doctrinal feuds (if at a lower level while under 'external threat'). They tend to not have a single revelationary source, but rather listen to certain revered Soul-bearers' guidance regarding what sorts of behavior leads to 'lightness'. This can be a problem, as occasionally revered Soul-bearers have been co-opted either subtly or overtly for use in subversion attempts against One Soul believers.
Materialism - Text by M. Alan Kazlev Religious or philosophical system that asserts that the physical universe of matter and energy, is the only reality. Popular in a number of polities and empires. The most widespread and popular is MPA Materialism, which asserts that the material world has endless possibilities and these can be manifested through action.