"Change is always uncomfortable, that is human nature, but change is necessary to progress and evolve."

Kesha has become a voice for activism and social justice with the release of her track "Here Comes the Change," featured in the upcoming Ruth Bader Ginsburg biopic On the Basis of Sex, out on Dec. 25.

Starring Felicity Jones, the film follows Supreme Court Justice Ginsburg's lifelong fight for women's equality from her days as a young mother and Harvard Law School student in the 1970s. After her husband, tax lawyer Martin Ginsburg learns that he has testicular cancer, she attends his classes in addition to her own, typing and reading notes for him every night to make sure he does not fall behind due to his illness. Later on, Martin becomes Ruth's biggest advocate throughout her career, suggesting a discriminatory tax case to propose her argument for women's rights.

Kesha's "Here Comes the Change" appears during the end credits for On the Basis of Sex, where she further reinstates the idea of change through lyrics like "Is it a crazy thought/ That if I had a child/ I hope they live to see the day/ That everyone's equal."

Earlier this year, the 31-year-old singer released a moving lyric video calling for activism and change through voting. The official black-and-white music video that followed includes Kesha's stripped-down acoustic performance of the song in an empty house with photos of famous civil rights activists alongside Justice Ginsburg.

Billboard caught up with the singer-songwriter via email to discuss the inspiration behind "Here Comes the Change," the importance of activism, and the lessons she's learned from Ginsburg's legacy depicted in On the Basis of Sex.

In On the Basis of Sex, Ruth Bader Ginsburg brings about a wave of change. Was there a specific scene in the movie that stuck with you while writing the song?

I don’t want to give anything away, but there is a moment in the film when you see present-day RBG, and when I first saw that scene it shook me because you are taking this ride with this amazing film and then all of a sudden you are hit with the reality that this isn’t made up, and we have not yet come to the Hollywood ending of this story. This is the real history of one very amazing woman’s determination to fight for equality, and she continues to do so currently. I think the most inspiring part of the film, and Justice Ginsburg’s legacy, is that it shows that one person can make a real change. Her drive and ambition was infectious -- it has made me want to be a better person -- one who is more politically inclined and really pays attention to the choices I make and how they will affect other people.

What made you decide on the name of the song and what change do you feel is coming?

After I saw the movie, I wanted to write a timeless song -- a song that would have been relevant in all time periods. We are always going to have to fight for equality, there’s still a lot of work to be done but we are never going to give up. So saying “Here Comes the Change” is just that affirmation that if you think we will get tired and give up on this fight you are wrong. Change is always uncomfortable, that is human nature, but change is necessary to progress and evolve.

What inspired the video’s aesthetic with the hollow walls, your decision to wear a super feminine, embellished dress with frills, etc.?

I wanted the video to feel as raw as the song and for the visuals to evoke a sense of frustration and loneliness meeting hope and conviction. We chose to shoot in an empty Victorian home, which felt compelling because it was historic and lonely. Visually I wanted to shoot with natural light with my freckles showing and natural hair. We wanted to strip everything else away so it was just about the performance. The house we filmed in is also a home Dolly Parton filmed a movie in, and being a huge fan of hers I felt as if there was some residual magic still in the air from her.

In the movie, Ruth Bader Ginsburg is constantly confronted with the question, “Are race and gender the same?” And in the music video, there’s a scene with photos of famous figures who fought for civil rights, both men and women, including Ruth. Why did you choose to use that and include her?

I feel as if we are always fighting for equality. The identity of the oppressed is constantly changing faces, from that of women fighting for the right to vote to racial minorities fighting for equal rights, to transgender people fighting for their right to serve in the military -- it's all an ongoing fight for equality that is never done, but the common thread is that we simply want equality. Period. No matter the color of your skin or the country you were born in or your gender identity or anything else. It's about equality for all people. Sadly the fight is far from over, but the strength to fight is far from gone.

The lyric video includes young women protesting in the '70s -- was this also inspired by the movie and/or RBG’s daughter Jane in the film, who shows RBG that the times are changing?

I absolutely loved watching Jane come of age in this film. Another scene that has stayed with me and gives me goosebumps just thinking about, is when Jane, Ruth’s daughter, stands up for herself in the pouring rain to men cat-calling her and her mother. It was a pivotal point where Ruth is realizing that culture changes and evolves and that the law should reflect that. The law should not hold any person back or discriminate on the basis of sex, gender or race. Ruth realizes that the law must change with the culture, to allow people to be the best version of them self, Dream as big as they could imagine and try to reach their greatest potential.

With the lyric video we wanted to create scenes where current-day protesters are essentially marching with the ghosts of those who came before them. The message will be that the long, proud tradition of American social activism is alive and well. It’s being passed on to the next generation and is as important as ever.

With Ruth Bader Ginsburg’s lifelong work still unfinished, what work do you feel is next for the new generations of men and women? And how do you plan to be part of that?

I hope audiences take away a sense of the amount that one person can do. You see one woman do so much and it’s so incredible if you are impassioned and believe you can do something and you try to do something, you can make change. One step at a time, one case at a time, one act of kindness at a time. And it’s not all easy, it rarely is, but just keep fighting.

Check out Kesha's video for "Here Comes the Change" below.