In a press conference last Thursday, Speaker of the House Nancy Pelosi declared that there's "a moral obligation for us to hand this planet over to the next generation in a responsible way."
“For me," she stated, "it’s a religious thing: I believe this is God’s creation, and we have a moral obligation to be good stewards.”
So far, so good. It's a standard Christian theological position that the creation has been placed under man's stewardship and that we have a duty to properly care for it.
But then Ms. Pelosi added that those who don't share her belief that God has laid upon humanity the duty to care for the earth nevertheless still have an obligation to do so: “If you don’t share that view you must share the view that we have an obligation to future generations."
Here, regardless of what we think about climate change, green energy, etc., we might raise a philosophical eyebrow. Speaker Pelosi believes that God has imposed a moral obligation upon us to keep the planet healthy, but what has laid that obligation upon us if those who don't share the view that it was imposed by God are correct?
What is the source of a moral duty to future generations if not God? Why should people today not just live for themselves, maximize their own comfort and well-being and let future generations fend for themselves?
Indeed, we might harbor a deep concern for our great, great grandchildren's well-being but from whence comes an obligation to do so?
Ms. Pelosi makes a common mistake in her press conference. She assumes that God is just one source among others of objective moral obligations whereas in fact, God is, and can be, the only source of objective moral obligations (An objective moral obligation is one which exists whether or not we believe it does).
If God doesn't exist or is irrelevant to how we live, then living just for oneself is not wrong in any moral sense. There's no obligation to sacrifice for others, especially others who will not be born for another hundred years.
If one believes that we do have such obligations as Ms. Pelosi describes, then, like her, one should be a theist since objective moral obligation does not sit at all comfortably or consistently in a naturalistic worldview.
The Speaker would've been on firmer ground had she said something like, "I believe God obligates all humanity to care for the planet and that God will hold us responsible for how we treat the planet. You may not share that belief but God obligates you nonetheless."
That may've sounded a unpleasantly dogmatic to contemporary ears, but it would've had the merit of making more sense than assuming that there could be some other source of a duty to care about the well-being of future generations.