There are four words etched in stone above the entrance of the Supreme Court building. “Equal Justice Under Law.”

The essence of this engraving will permeate the highest court in the land this week as the nine justices hear arguments that could effectively reshape how the United States defines marriage. I want to give you all a quick run-down of what exactly the Court will be deciding and the possible consequences of potential decisions.

But I will also end this post with a quick word in favor of same sex marriage. As a firm supporter of gay and lesbian couples’ right to marry, like 73% of the rest of my generation, I can’t help but urge the Supreme Court to make 2013 the year it was on the right side of history.

Tuesday’s hearings involve the California ballot initiative Proposition 8, which banned same sex marriage in the state after a brief period when it was legal for gay Californians to wed. Wednesday, the court will hear arguments surrounding the Defense of Marriage Act, which federally defines marriage as a union solely between a man and a woman, barring same sex couples (even those legally married in their states) from federal benefits to married couples, such as tax breaks and survivors benefits.

Apart from upholding Prop 8, which would continue to give states the freedom to ban same sex marriage, the Supreme Court could rule that the ban is unconstitutional on the grounds that California was not allowed to take away a right to same sex couples once the California Supreme Court guaranteed it. Under this ruling, same sex marriages would once again be legal in California, but only in California. However, there is another, more sweeping decision that the Supreme Court could make. It could deem Proposition 8 unconstitutional based on its withholding the title of “marriage” from same sex unions with otherwise equal state benefits. In this case, any “everything but marriage” civil union law, currently in place in 9 states, would be unconstitutional, and same sex couples in civil unions in these states would gain the title of “marriage.”

Wednesday’s hearings may have much greater impact on the national definition of marriage because the focus will be on the 1996 Defense of Marriage Act. Signed into law by President Bill Clinton, who this month called for the law’s repeal, defines marriage as between a man and a woman nationwide. If the law is upheld, the current system remains the same. If the law is deemed unconstitutional, gay couples married in the nine states where same sex marriage legal would become federally recognized as married and become eligible for federal benefits. This is a sweeping decision gay rights advocates are hoping for, but some justices seem hesitant to rule.

The four liberal justices, on the bench seem to align with gay rights supporters in their approval of same sex marriage, while four notable conservative justices seem more hesitant to rule a broad redefinition of marriage.

The justice to really watch in this debate is Justice Anthony Kennedy, who was appointed to the Supreme Court by Ronald Reagan. Although a marked conservative, Kennedy has written 2 opinions in previous cases that greatly advanced gay rights, one rejecting the criminalization of homosexual acts and another that protected antidiscrimination policies for LGBT persons in Colorado. He has even been quoted saying, “a state cannot so deem a class of persons a stranger to its laws.”

And this is where I get into my opinion.

As the nine justices take their place on the bench these next few months, I hope they look back at their history. Since 1888, the Supreme Court has declared that marriage is a fundamental right of all citizens.

1974. Cleveland Board of Education v. LaFleur. “This Court has long recongnized that freedom of personal choice in matters of marriage and family is one of the liberties protected by the Due Process Clause in the 14^th Amendment.”

Couldn’t have said it better myself. While sexuality is not a choice, it is a choice to enter a long-term committed relationship with the person you love. And a noble choice at that.

1996. M.L.B. v. S.L.J. “Choices about marriage, family life, and the upbringing of children are among associational rights this Court has ranked as ‘of basic importance in our society,’ rights sheltered by the Fourteenth Amendment against the State’s unwarranted usurpation, disregard, or disrespect.”

No further explanation needed.

The Supreme Court has defined marriage as a fundamental right, and its core duty is ensure the equal rights of all Americans guaranteed by the Constitution.

Some wishing to keep Proposition 8 and DOMA in place aren’t even arguing against the actual idea of same sex marriage. The avenue they’re taking is one of leaving it up to the states to decide. That, in and of itself, is a big progression.

We have seen where the tide is turning. We have seen how people’s opinions on this matter are changing. Notable politicians from both parties are coming out in favor of same sex marriage. 100 Republicans signed a brief supporting same sex marriage and sent it to the Supreme Court weeks ago. A new CNN/ORC poll has found that 53% of Americans support legalizing same sex marriage, the highest ever in the nation’s history.

Thomas Jefferson was right when he said, “laws and institutions must go hand in hand with the progress of the human mind.” America is making progress. Our views are changing. According to Jefferson, as our minds become “more developed, more enlightened, as new discoveries are made, new truths discovered and manners and opinions change, with the change of circumstances, institutions must advance also to keep pace with the times.”

Marriage is an institution all citizens should be able to enter into. Jefferson said it well. It’s time for this institution to advance.

“Equal Justice Under Law.” Four short words etched into the Supreme Court. Four short words that the highest court in the land should truly set in stone.