Obama Ruth Bader Ginsburg (AP)President Obama has a tough choice to make when it comes to replacing the late Supreme Court Justice Antonin Scalia.

Does he appoint a person of color to increase diversity? A Republican to show diplomacy? What about a non-human justice? We hear robots have come a long way.

Logically, however (and maybe ethically, practically, and historically, too) one decision is clear: Regardless of race, sex, or age, Obama should put an atheist on the bench.

Hear me out.

If for no other reason, having an openly atheistic justice sends an official message that non-believing people can be morally right — in a country where a person's goodness is often equated with the depth of their faith.

The job of the Supreme Court is, in effect, to continually revise America's mission statement. Justices helped dismantle segregation in schools, uphold free speech in its most extreme forms, and legalize same-sex marriage. Appointing an atheist justice bolsters that move toward progress. It says good ideas — just ideas — can come from anywhere.

A little context: Americans may be losing their religiosity, but they're still overwhelmingly devout.

According to Pew research data, approximately 70% of people identify as Christian, while 23% declare themselves atheist, agnostic, or nothing at all.

This high concentration of faith trickles into people's political views. A separate Pew survey released last month found that half of Americans would be less likely to support an atheist president, and only 6% saw a lack of religious belief as an asset.

The logic here seems to be that since atheists don't put their faith in a higher power, religious Americans don't put their faith in atheist leaders. 

But that ignores the fact the US was founded on secular principles, and that religion doesn't own the capacity for acting ethically. It's free for the taking. Having an atheist justice fill Scalia's seat would help remind Americans of that lost insight.

On a more granular level, appointing a non-believer reassures people that phrases like "non-believer" aren't inherently negative. Instead, they can come to see that atheists, in the absence of a holy book to guide moral decision-making, rely primarily on reason.

It would show that nonbelieving justices are capable and reasonable and every bit as compassionate as believing justices. And it would validate the pursuit of truth and fairness over ideological bias — something atheists and the Supreme Court naturally have in common.

As cosmologist Lawrence Krauss wrote in a recent New Yorker column, an atheist justice "would have different intellectual habits" and would use fact-based, empirical evidence to assess specific cases. There would be less dogma to cloud the justice's opinion, less reliance on personal experience over legal expertise. 

An atheist judge would probably ruffle the majority's feathers, especially if the justice is openly secular. A 2013 survey, for example, found that 81% of Americans believe a justice's religious beliefs influence his or her opinions.

In the same way Lady Gaga serves as an icon for gender fluidity, and Beyonce for black and female empowerment, an atheist justice (however less cool) would show atheists aren't some abstract nefarious force. Some may be more militant in their non-beliefs than others, but the law depends on stone-cold reason, which is pretty much all atheists have to go on.

Breaking down the stigma of atheism in politics won't happen immediately; societal attitudes change at a glacial pace. But justices can serve until they die. America and its new non-believer would have plenty of time to get to know each other.