Amazon CEO Jeff Bezos has seen his wealth skyrocket in recent years—his latest milestone being his net worth amassing over $150 billion.

But, this fact sits uncomfortably with another one—that millions of people, especially in developing nations, are dying from causes that are easily eliminated with sufficient funding. Through organizations like Seva and the Against Malaria Foundation (AMF), cataracts can be treated for $50, malaria can be prevented for $2, and children can be dewormed for as little as $1 in the developing nations in which they operate.

Yet, these services often go unprovided, as the wealthy among us continue to get wealthier.

I don’t just mean the filthy rich like Bezos. If you are reading this article, chances are you have money to spare, inessential purchases that could be replaced with donations to charities providing the above mentioned essential services. The question is—do we as wealthy people have a moral obligation to give our excess money to potentially life-saving causes?

Most people would probably say no, reasoning that people who work for their money should be able to spend it however they please. But the average person would also disagree with the logical conclusions behind this reasoning.

A thought experiment popularized by philosopher and ethicist Peter Singer in the 1970s perfectly demonstrates why this reasoning is inconsistent with our moral values. The experiment goes roughly as follows:

Imagine you are walking down the street in brand new $100 shoes. As you walk, you see a child drowning in a fairly deep puddle. The puddle is not so deep that you risk any harm to yourself, but stepping in it and rescuing the child will ruin your new shoes.

Assume there is no way to both prevent your shoes from getting ruined and saving the child’s life—are you obligated to save the child?

Our society would rightfully treat the cold-hearted hedonist who wouldn’t save the child as a monster—but here’s the fun part of the experiment: assume you would save the child. You just sacrificed $100 to save a life.

Donating $100 to the Against Malaria Foundation could buy, transport and strategically place 50 bednets amongst some of the world’s poor, ensuring that 100 people do not get malaria, which still kills 438,000 people annually.

Does the fact that your money is going towards saving someone overseas, rather than in front of your own eyes, make much of a difference? In both instances, sacrificing a relatively small amount of money could save lives.

The idea that we should spend our money to do good in the world rather than on frivolous, if often charming, products, has roots far beyond that of Peter Singer’s Famine, Affluence And Morality—the controversial book from which the above thought experiment was taken.

It has roots in the golden rule, which in turn has roots in ancient human history.

Doing unto others as we wish to have done to ourselves means spending money in an unselfish manner—to potentially save lives, rather than on unnecessary luxuries. 

This raises something of an impossible ethical standard. Giving any money not used for absolute essentials is a difficult goal, but that doesn’t mean we shouldn’t at least to try to share our wealth with those who are less fortunate.

Take small steps—instead of getting a coffee every morning, opt out once in a while and donate to a worthy cause. One day, you might have spent enough in donations to save a life.