Hi j-t,
The survive line was intended as a base Darwinian hypothesis. A firm foundation.
It does not preclude the step up to thriving.
But it avoids statements like those made by Jefferson about being endowed with certain unalienable rights.
I don't think you could make a statement about nature providing humans with a destiny that includes life, liberty and the pursuit of happiness after the Origin of Species was published. Those are the kinds of goals that mankind sets for itself but which nature, to a great extent, opposes. The anopheles mosquito distributes its malaria to unwitting victims. The wasp inserts its larva into the poor caterpillar.
But it's not all bad news.
These days, many evolutionary scientists and mathematicians tell us that the combination of trustworthy individualism and group altruism is the most efficient form of multiparty relationship.
It isn't such a leap to extrapolate this model to human society and economics as a whole. By encouraging cooperation, we create wealth. And by creating and sharing wealth, we remove ourselves from the minimal Darwinian environment and enter a zone with more opportunities for happiness.