Girls interrupted

My girlfriend and I went on a "study date" on the LES. We spent most of the time doing work, but every once in a while you have to come up for air and complain or gossip about boys. Apparently this is irresistible to guys within earshot, as we were interrupted not once but twice.

Once:
Friend: "Ugh, this stack of Kant papers is killing me."
Me: "Yeah? Give some to me."
Random guy: "Hey, sorry to interrupt - are you guys in philosophy?"
Me: "Yes."
Random guy: "Okay, I have a question. I'm reading Caesar's Commentary on the Gallic Wars, and - what's it called when someone draws some conclusion about something, like based on past evidence?"
Me: "An inference. Or an inductive generalization."
[I won't bore you with the logic lecture that followed.]

Twice:
Friend: "So the Russian texted me again. What do I do? Do I text the guy back? Not text him? What do I say?"
Random guy: "How many times did you go out with him?"
Friend: "Once. But then we texted a few times afterwards."
Random guy: "Yeah, you don't have to text him back."
Friend: "Really?"
Random guy: "If you've gone out fewer than three times, you don't have to return his calls or texts. On the other hand, if you've gone out with a guy three or more times, and then you just disappear, that's a problem, because at that point he's made an investment and now he's left wondering what happened."
Me: "This sounds right. Write this down."