And what about the larger cultural framework? How do you tackle these concepts in a world where women are empowered to say yes — but taught that they must be coy when they do it? When they’ve been socialized to think that “yes” means you’re a slut, “maybe” means you’re a tease, and “no” means you’re a prude — or that, from the male perspective, as one friend recently put it, “no is always negotiable”?

“I think that if you’re going to teach about consent, you need to also talk about culture,” said Jing Qu, a junior at Columbia who has been involved in activism around consent education on campus. “It’s the oversexualization of female bodies on TV and in magazines. It’s this idea of like: ‘Oh does she want it? She won’t give me a straight answer.’ It’s the idea that she’s ‘asking for it.’ It’s literally like Justin Bieber saying” — while rolling around half-naked on a bed with a woman in his new video — “‘What do you mean?’” (It’s the title of his new song.)

Mr. Kalin, for what it’s worth, tries to fit his talk into the bigger context. Back in the auditorium, he asked the Trinity students which nights were the “party nights” on campus.

The room was silent.

“Now tell me: On a party night, before men go out, what do we tell them to do?” he asked.

“What about women?” he said. “What do we tell them to do before a night out?”

The students suddenly became animated.

“Stick together,” a woman in the front said.

“Travel in groups,” another called out.

“Don’t put down your drink.” “Dress appropriately.”

“Put your keys between your knuckles.”

Mr. Kalin nodded. “Does anyone have any idea where I’m going with this?”