As is human nature, we often want what we can't have, and vacations are hardly exempt from this desire. (cardrates.com)
But again, human nature is human nature and if you're getting beat up all the time. (seganerds.com)
If by human nature all you mean is whatever humans do, then absolutely there's a human nature, and an evolutionary perspective on human beings will inform us about human nature. (scientificamerican.com)