People crave togetherness. But what happens when friends disagree about how much is safe?

Humans are hard-wired for social connection, he says. It’s primal. If your friends want to cook out and you’re not ready, well, you can partially blame biology.

“Our brains are very sensitive to the distress of: Nobody’s around me. There’s nobody I can depend on if I get into trouble,” he says. It rings our fight-or-flight alarm bells.

But lately, those alarm bells often come from rogue pals and neighbors. In Bellingham, home day care operator Kari Phaneuf allows her young daughter to play and barbecue with certain families, after a period of quarantine. People bring plates; nobody ventures inside. A neighbor saw the children together and yelled at Phaneuf. It seemed that her own granddaughter was shunned from the group by a selective parent.

“[The grandmother] wanted her granddaughter to be included. I had no problem with it, but another neighbor didn’t think it was a good idea and said she couldn’t go over and play. It’s a small street; you can’t miss anything,” she says. “I felt badly about it.”

In Lexington, Bobbie Carlton “committed a faux pas without thinking,” she says. She lives in a neighborhood rife with high school seniors. To celebrate graduation, she suggested a goodie program, wherein sweets fairies would drop treats at doorsteps to celebrate.

“I was told, ‘We don’t share food with anybody,’ ” she recalls. “People were far kinder than I’m making it out to be, but, oh God. I’m a moron.”

In Townsend, Edrie Edrie got a surprise phone call from another mom. The mother and her young daughter had spontaneously shown up outside for a visit — leading to a meltdown from Edrie’s 5-year-old, who couldn’t see her best friend.

“I didn’t have any of my normal equipment ready. I was preparing to go get groceries, and all of my stuff was in the car. We couldn’t go outside to say anything. With more prep it would have been easier. I’ll feel comfortable when there’s a vaccine,” says Edrie, who has an immune disorder.

Somerville’s Matthew Petersen changed his Twitter handle to “Matthew Petersen Is Staying Home” — a small, visible way to show he takes social distancing seriously.

“I don’t see myself doing anything with a group for a while. My roommates work in health care. It would be irresponsible,” he says. Instead, he bakes bread.

“I’ve baked more than I ever have in my life,” he says.

So what’s safe? Can we have a burger with friends? Order pizza and sit on someone’s lawn? Or must we bake bread in isolation for the immediate future?

“I’m more worried about people than pizza,” says Dr. Abraar Karan, a physician at Harvard Medical School working on the COVID-19 response in Massachusetts.

“Theoretically, if someone sneezes on your burger, it could be a route of transmission. But it’s not the primary mode … and you only have so much worry you can sustain. The real transmission risk is [through] extended face-to-face contact via large droplets and small airborne particles,” he says.

Just go light on the booze. Risk increases when people get tipsy and opt to enter someone’s home, he says, maybe to use the bathroom. A crowd forms in a hallway; people chat close together and handle common surfaces.

“Avoid crowds and extended face-to-face interactions, and avoid them especially indoors,” he says. “The risk in terms of any socialization is that outdoor situations can turn indoor quickly.”

Also bring your own utensils to avoid sharing objects, such as serving spoons, bowls, condiment jars, and spatulas. Indeed, now might be the time to retire the dreaded potluck with its communal vats of curdled mayonnaise and egg salad once and for all.

“The food itself is probably OK, subject to all the usual food safety rules. But not the spoon you’re using to scoop the salad or the jug of lemonade, grabbing the same handle,” says Dr. Eleanor Murray, an assistant professor of epidemiology at Boston University School of Public Health.

Murray frames social safety in four dimensions. The more space someone maintains, the less risky an encounter becomes. Time spent together is also a factor. Less time means less risk. Place is also important; outdoors is safer than indoors. Finally, people are important. Consider who you’re comfortable with and who practices similar distancing protocols.

“It will be a long time before we’re in a zero-risk situation, but we also do need to get back to a little more routine life, with some socialization. It’s important for mental and emotional health,” Murray says. “Think about the pieces you’ve been missing and the people who are most important. Don’t see friends of friends; think about key friends you’ve missed.”

Of course, this requires diplomacy. You may need to turn down a friend’s kind offer of tuna sandwiches or well-meaning invitation to loll in their new inflatable pool.

When you do reject an offer, “Diplomatic honesty is the way to go,” says Janet Parnes, a social conversation and etiquette consultant in Millis, whose skills might soon be in high demand. Parnes favors the “bad news sandwich” framework of rejection: two positive comments bookending a negative one. So, for instance, “That [suspicious food item] looks so tempting. However, the virus is still out there, so I’m being particularly cautious. Another time, I’d love it.”

If you’re pressed by a pal who doesn’t understand your concern, Parnes suggests blaming yourself.

“Say, ‘I’m really strict; I’m stricter than a lot of people are. I’m more nervous than other people are,’” she says, which is tough to dispute.

Awkward? Maybe. But muddling through new social interactions might make us live more deliberately, pinpointing activities (and people) we value, says Nobel. Perhaps we will emerge calmer and with more self-knowledge, less eager to jam our schedules or gullets with extraneous froth.

“One positive possibility is people will develop new skills and new ways of connecting authentically with others,” he says. “The silver lining is that we’ll develop insights into positive experiences and habits to engage on a daily basis. And, as we all go through a common crisis, it unites us. It might generate a level of social intimacy that allows people to be authentic in a positive way,” he says.

Kara Baskin can be reached at kara.baskin@globe.com. Follow her @kcbaskin.