Lifeboat ethics is a metaphor for resource distribution proposed by the ecologist Garrett Hardin in two articles published in 1974, building on his earlier 1968 article detailing "The tragedy of the commons". Hardin's 1974 metaphor describes a lifeboat bearing fifty people with room for ten more. The lifeboat is in an ocean surrounded by a hundred swimmers. The ethics of the situation stem from the dilemma of whether (and under what circumstances) swimmers should be taken aboard the lifeboat.