The sociologist Herbert Spencer is credited with the phrase "survival of the fittest," which he applied to biological evolution years before Darwin's "Origin of Species," and also to the evolution of society. As an agnostic, he also rejected the notion of a divine being, at least insofar as it is possible to say anything meaningful (or empirical) about it.
Likening society to an organism, Spencer emphasized that it should be permitted to develop organically, without the intervention of the State. Spencer argued in favor of natural rights that would allow individuals to do as they thought best.
His political philosophy of decreased state power continues to influence libertarians and other political thinkers critical of the government's impact on individual rights.