Driverless cars ponder who should die first

Impossible choice: People say they are less likely to buy a car programmed to save pedestrians over its driver.

Are some lives worth more than others? The rapid development of self-driving technology is raising questions about who should be saved in car crashes, and bringing up old ethical dilemmas.

A self-driving car carrying a family of four is careening towards a brick wall. It can either stay on course and sacrifice its passengers, or swerve and hit a pedestrian. What should it do? Now, imagine the pedestrian is a violent criminal. Does that change your view? What if it’s a baby in a pushchair?

To help explain the problem, scientists have analysed more than 40 million responses to scenarios like this.

They were “trying to understand the kinds of moral decisions that driverless cars might have to resort to,” says researcher Edmond Awad.

The results reveal that we would prefer to save a baby above anyone else. A criminal is considered more valuable than a cat, but less so than a dog. While “large” people are less likely to be saved than an average person, their lives are valued above the homeless.

These issues were first raised by the trolley problem, a classic ethical dilemma set out by philosopher Philippa Foot in 1967.

In the problem, a runaway tram is on course to hit five people who are tied to the tracks. You are standing next to a lever. If you pull it, the tram will be redirected on to a side track, but one person is tied down there. What do you do?

Some might say five lives are worth more than one and pull the lever. Another could argue it is best to do nothing because it is wrong to kill.

While these questions sound hypothetical, the reality may not be far off.

Are some lives worth more than others?


Absolutely not, say some. Every life is equally precious. It is morally wrong to say that someone is less deserving of life because they are old or homeless or have a criminal past.

Don’t be naive, reply others. Surely it is better for an elderly man who has lived a rich and full life to die in the place of a baby who has barely seen the world and is full of potential.

You Decide

  1. Should we fear the future of self-driving cars?


  1. Look at the graphic at the top of this article. Take the types of people listed and put them in order of who you think it is most to least important to save. Think about how you can justify your decision. Then, get into pairs and compare your lists. How different are they from our graphic, and from each other’s?

Some People Say...

“Ethics is knowing the difference between what you have a right to do and what is right to do.”

Potter Stewart

What do you think?

Q & A

What do we know?
The Massachusetts Institute of Technology (MIT) has created a “Moral Machine” to study which lives people think are the most worthy of saving in a car accident with two possible outcomes. One day, self-driving cars may have to make these decisions.
What do we not know?
Whether these dilemmas will ever be played out in real life.

Word Watch

The research was carried out by the Massachusetts Institute of Technology and translated into a graph by the World Economic Forum.
The trolley problem
A variation of this problem involves the choice of whether to push a fat man onto the tracks to save the five people. This can provoke different responses as many people view this as more active murder than pulling the lever.
An imagined situation to test a theory, rather than something real.

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