felicific calculus

Let us imagine you are a doctor driving to a patient, a young mother who is about to give birth. It looks like she will need a Cesarean Section It is late at night and you come across a car accident on the country road you are travelling on. Two cars are involved in the accident and both drivers are unconscious and have visible injuries. One of the men is the father of the child you are going to deliver, and the other man is very old. You do not know the extent of their injuries but in your opinion, without immediate medical help, one or both may die. You as a Utilitarian are now faced with one of three possible solutions:

1. You help the young mother who's about to give birth.
2. You help the young woman's husband.
3. You help the old man.

The outcome of felicific calculus would suggest:

1. Attending to the mother first is your primary concern as the doctor. The death of both mother and child is almost a certainty if you do not act now, whereas the death of the men is uncertain. Furthermore, the pain of the mother is clearly greater than that of the men at this time. There is a greater richness and purity in saving the life of a young child who has, in all probability, a long happy life ahead. Therefore the extent and duration of the utility created by these two people is a clear likelihood.
2. Attending to the young husband is the next priority. The pleasures of a new family—its intensity, duration, extent, richness, and purity—are all clear probabilities. If, as the doctor, you attend him first his wife and child would in all probability die. The man would then experience pain. The pain experienced by the widowed husband is likely to outstrip any pleasure to be gained from continued life without his loved ones.
3. Attending to the old man is the last priority. The duration and certainty of his future pleasure are questionable owing to his age—he has all but lived his life. This is sometimes known as the 'good innings' argument, according to which the older you are the less claim you have to life.

Certainly, the doctor should not be limited to the three choices, though the whole purpose of the exercise rests on it being a closed universe. To maximize the felicific calculus, he should try to secure external help by calling another doctor to help the mother, and by asking people nearby and the emergency services to deal with the accident.

Some critics argue that the happiness of different people is incommensurable, and thus a felicific calculus is impossible in practice.

Wikipedia