Assuming
you mean "social Darwinism," there is no similarity. Social Darwinism
postulates that those members of society who have the most social value
will prosper and that social failures will breed less (have fewer or no
children).
Paternalism postulates that it is morally better to help social
unfortunates, including extending their lives and breeding opportunities
(help them to have more children who survive and perpetuate their gene
lines).
hope this helps :)