The government of Switzerland kicked off a debate this week when it ordered that lobsters and other crustaceans no longer be dropped alive into boiling water. Boiling them causes pain, the government said, and should be replaced by a more rapid method of death — such as stunning.

Still, even the scientist who conducted the foundational research for the government’s decision said he’s not 100 percent sure that lobsters can feel pain. But he’s concerned enough that he’s only cooked a live lobster once and doesn’t plan to do it again.

“There’s no absolute proof, but you keep running experiments and almost everything I looked at came out consistent with the idea of pain in these animals,” said Robert Elwood, professor emeritus of animal behavior at Queen’s University in Belfast, Northern Ireland. “There should be a more humane approach with lobsters.”

Dr. Elwood’s position — and the Swiss government’s — is outside the scientific mainstream, said Joseph Ayers, a professor of marine and environmental sciences at Northeastern University in Boston.