Think back to the last meaningful conversation you had. A conversation that made you question your way of thinking. Was it about time? Space? Life?

For me, that last conversation was with Calvin—a 47-year-old man who lives without a home. My roommate described him as "an old soul; like a modern-day Socrates". I met this modern-day Socrates while volunteering at the downtown Portland location for "Operation Nightwatch," a place where people who have little to no shelter can go to feel safe, grab a sandwich, and socialize.

My job as volunteer was to hand out food, clean tables, and talk to as many people as I could.

Calvin was one such person; here's what we talked about:

1. Listening

Me: "What does it mean to listen?"

Calvin: "When you listen to someone, you look into their eyes because the eyes are the windows to the soul. You look up when you're thinking, because that's where your brain is; where your thoughts are. You're present. Not distracted, not thinking about cats or something."

Me: "So if I'm talking to someone and they're on their phone, or vice versa, are they really listening?"

Calvin: "Right now Elizabeth, we are the most important people in the room. I'm listening to you, and you're listening to me. You're giving me a gift with your presence.So if hypothetically, you go out with your friend and she's texting her boyfriend, then who is the most important person in the room to her?"

Me: "Her boyfriend! So then if she's not looking into my eyes, and she's distracted, then she's not really listening to me."

Calvin: "Exactly! You've answered your own question."

2. Community

Calvin: "What is 'community'?"

Me: "Well a community is a group of people that support one another. They might not text each other all the time, but they're still there."

Calvin: "So the KKK is a community?"

Me: "What? No!"

Calvin: "I'm just kidding. Would you like to hear my definition?"

Me: "Sure!"

Calvin: "Community is a combination of the words "common," and "unity". Common refers to something we all share, and unity refers to "union" or "together". Who is your worst enemy?"

Me: "I guess...me?"

Calvin: "And who is your best friend?"

Me: "Also me?"

Calvin: "Right there-- you are a community. You are yourself, your worst enemy, and your best friend."

Me: "So kind of like Sigmund Freud's id, ego, and superego?"

Calvin: "Kind of like that! You know, my friend would really like to pick your brain. He loves that kind of philosophical thinking, and he's highly intelligent. But also very dangerous."

Me: "Why is your friend dangerous?"

3. Why Calvin's Friend Is Dangerous

Calvin: "When you think for yourself, and you don't let others speak for you or dictate your actions, you become dangerous. In a good way! You can become dangerous too, Elizabeth."

4. Time

Calvin: "How many months are there in a year?"

Me: "12."

Calvin: "How many weeks?"

Me: "52."

Calvin: "How many minutes?"

Me: "525,600."

Calvin: "Do you know why that movie Rent was so important? Because it's about time. It's about how we spend our time. There are 525,600 minutes in a year. Think about how many of those minutes we waste."

Me: "Oh, I know I waste a lot of time..."

Calvin: "I do too. This conversation will never happen again. We will never get this time back. And that's okay. But that's also why we have to be present, and not waste time."

5. Why Calvin Will Always Feed His Enemy

Calvin: "When I was younger, I walked by a man who was homeless. The man was sitting in front of a burger shop. I remember having two dollars in my pocket. I could have given that man a dollar so he could get a burger, but I didn't. I left him to rifle through the trash. So even if you are my worst enemy, I will still break bread with you, because if I didn't, I wouldn't be honoring that man."

6. How Calvin Celebrates

Me: "Do you celebrate Thanksgiving?"

Calvin: "I don't celebrate occasions: I celebrate people."

Me: "How so?"

Calvin: "I'm probably the only man you'll ever meet that does this, but every April 28th I have a cranberry cocktail to honor the first woman I ever loved. That was her favorite drink. What's your favorite drink?"

Me: "A Shirley Temple."

Calvin: "I haven't had one of those in a long time. I tell you what. If I never see you again, then every September 26th I will have a Shirley Temple in your honor."

Me: "What if you do see me again?"

Calvin: "Then we will drink Shirley Temples together."