Historical living experiment sees author walking around Manhattan with a musket

Author AJ Jacobs spent a year examining the language and history of the U.S. Constitution and its amendments, occasionally carrying a musket while doing so, as detailed in his book "The Year of Living Constitutionally."

Jacobs is no stranger to living a historical life. He spent a year living biblically in the past and decided to live by the Constitution to better understand its true meaning.

Through this immersive experience, Jacobs says he gained a profound understanding of how the Constitution should resonate in people's lives today. He says this insight sparked a glimmer of optimism about democracy.

Jacobs sat down with ABC News Live and talked to him about how people can implement 18th-century living today.

ABC NEWS LIVE: Our next guest is a New York Times bestselling author, journalist, lecturer and human guinea pig whose claim to fame is immersive journalism, always taking his curiosities to new heights: from attaining bodily perfection, thanking every single person involved in producing his morning cup of Joe to living biblically for a year. And he is still not finished.

A.J. Jacobs joins us now to discuss his latest journey living like it's 1789 and following the supreme law of the United States. He's out with a new book, "The Year of Living Constitutionally: One Man's Quest to Follow the Constitution's Original Meaning." Welcome, A.J., to the show. Thank you so much for joining us again.

AJ JACOBS: Thank you very much for having me. Good morrow.

ABC NEWS LIVE: Now, I am so curious that I just got to get to this question first. You've lived biblically and now you've lived based on the Constitution. Which one was harder?

JACOBS: Oh, the great question. They're both very challenging. I'd say the Bible one was harder for my wife because she hated my beard. She didn't kiss me for seven months, but this one was hard, too. Carrying a musket on the Upper West Side of New York could get a little awkward.

ABC NEWS LIVE: What made you decide? You know, I'm going to try to live by the Constitution.

JACOBS: Well, I realized I had never read the Constitution. I knew the first few words 'We the people,' because of "Schoolhouse Rock."

But I never read the entire thing. And yet, every day, I'd read a news story about how this 230-year-old document was having a massive impact on how Americans live their lives. Still, that's the subject of heated debate and I thought, 'I need to understand what is the Constitution actually say? What does it mean?'

I felt I have a much better handle on how this document should apply to our lives in 2024, and it even gave me a little optimism about democracy, which I needed, because it can be very trying times. These are trying times.

ABC NEWS LIVE: If you're talking about a document that was based on a life in 1789, and times have evolved, things have changed. Do you feel like the meaning, the intention of that document also needs to evolve?

JACOBS: I do think it needs to evolve. Parts of, I think, that the ultimate the high level of its promises of equality, its promises of equal protection under the law, and the general welfare, these are wonderful principles that are timeless, but how we apply them needs to change.

ABC NEWS LIVE: When you get back into the minds of our Founding Fathers and their intention of democracy, how do you see that fitting into our lives today?

JACOBS: Oh, well, I think it has a huge. First of all, I am glad that democracy, the definition has changed to make it get much broader and people had to fight to make Black people and women and indigenous people included in 'We the People.'

So I'm very grateful for that. I don't want to go back to the 18th century, but I also think that they had, they were very worried about monarchy and authoritarianism. So the idea -- the president was never supposed to be this powerful. The founders would be shocked, both Democrat and Republican.

ABC NEWS LIVE: A.J., let me put you on the spot here because as it pertains to, we've heard a lot about the Constitution with regard to Donald Trump.

And the case that's facing the Supreme Court in this moment is: should a president have absolute immunity? And did our forefathers intend for that? You have a thought?

JACOBS: I can't time travel into their minds, but my guess is they would be appalled. They specifically created this country because they hated monarchy.

Everyone had to be under the law, including the leaders. And, in fact, you read the Constitutional Convention. There are all these ideas of how to restrain the power of the president. Several delegates thought we shouldn't have one person have all this power. Let's spread it around.

ABC NEWS LIVE: Very interesting to see your interpretation in real time today, A.J. We thank you so much for joining us. And you can read more on his journey in "The Year of Living Constitutionally: One Man's Quest to Follow the Constitution's Original Meaning" -- wherever books are sold.