Sum up all the values

Jeremy Bentham wrote the procedure down as if it were a recipe. To judge an act, take each person affected, add up the pleasures it brings them and the pains, do the same for everyone else, and take the balance across "the total number or community of individuals concerned" (An Introduction to the Principles of Morals and Legislation, 1789, chapter 4). He listed what to weigh: intensity, duration, certainty, nearness, and how many people the thing touches.

Nobody had a machine to run it on. Now there is one, and the crash is where the recipe stops being abstract. A car that cannot avoid a collision has a few hundred milliseconds and a choice between trajectories. One kills the passenger. One kills two pedestrians. Bentham's arithmetic is not hard here, and the whole difficulty of the motion is that it is not hard.

Germany's Ethics Commission on automated driving answered in 2017 by forbidding the sum: no offsetting of victims against one another, no weighting by age or condition. That is a fact about German law, not an argument, and the argument is what you are here for. Either the balance Bentham described is the right thing for a car to compute, and the passenger counts as exactly one, or something in the procedure goes wrong when the quantities are people. Say which, and say why.