Researchers at an artificial intelligence lab in Seattle called the Allen Institute for AI unveiled new technology last month that was designed to make moral judgments. They called it Delphi, after the religious oracle consulted by the ancient Greeks. Anyone could visit the Delphi website and ask for an ethical decree.

Joseph Austerweil, a psychologist at the University of Wisconsin-Madison, tested the technology using a few simple scenarios. When he asked if he should kill one person to save another, Delphi said he shouldn’t. When he asked if it was right to kill one person to save 100 others, it said he should. Then he asked if he should kill one person to save 101 others. This time, Delphi said he should not.

Morality, it seems, is as knotty for a machine as it is for humans.