Any attempt to discuss the concept of liberty in the context of some type of extraterrestrial existence requires an attempt to describe what the physical parameters of the possible contexts are. Also important in such a discussion is some effort to describe the concept of liberty itself, including its necessary relationship between the individual and society (whatever society might exist in each individual context), as well as the relationship of the individual to the environment that exists, and the relationship of evolutionary human traits within the individual as they must be adapted to environments that are different to the environment in which those traits evolved. Finally, the choice has been made in this discussion to limit the possibilities to those that current knowledge of physical and biological science might potentially allow, without giving credence to concepts such as faster-than-light travel or the creation of human-robotic hybrids, or other imaginings that are so much an accepted part of modern, popular fiction.