If there are no human rights a priori of government force, how can tyranny be avoided? In the absence of any deontological justification for normative ethics, there is only virtue ethics.
virtue
Transhumanist Virtue Ethics: Desirable Innate Preferences Determined by Reason
Natural rights don’t exist, except in the human mind. They are a way for a social species to maintain social cohesion. But, as useful as natural rights may be in deciding how to organize society, they are not fundamental; instead, they are derivative of what humans, in general, desire.