Must read article to understand AI in simple language. Today’s AI and machine learning is dependent on probabilistic correlations and not cause and effect learning. But “Correlations can often lead to insufficient or inaccurate conclusions. This point was clearly illustrated by an observational study on women’s health conducted in the 1990’s that concluded that Hormone Replacement Therapy (HRT) had a beneficial effect in mitigating heart disease. The same statistical view of the data also revealed a protective effect of HRT on homicide rates. When experts re-analyzed the data and adjusted for important confounding factors, they found that HRT actually had an adverse effect on heart disease and no effect on the homicide rate.”.

Three decades ago, a prime challenge in artificial-intelligence research was to program machines to associate a potential cause to a set of observable conditions. Pearl figured out how to do that using a scheme called Bayesian networks. Bayesian networks made it practical for machines to say that, given a patient who returned from Africa with a fever and body aches, the most likely explanation was malaria. In 2011 Pearl won the Turing Award, computer science’s highest honor, in large part for this work.

But as Pearl sees it, the field of AI got mired in probabilistic associations. These days, headlines tout the latest breakthroughs in machine learning and neural networks. We read about computers that can master ancient games and drive cars. Pearl is underwhelmed. As he sees it, the state of the art in artificial intelligence today is merely a souped-up version of what machines could already do a generation ago: find hidden regularities in a large set of data. “All the impressive achievements of deep learning amount to just curve fitting,” he said recently.

In his new book, Pearl, now 81, elaborates a vision for how truly intelligent machines would think. The key, he argues, is to replace reasoning by association with causal reasoning. Instead of the mere ability to correlate fever and malaria, machines need the capacity to reason that malaria causes fever. Once this kind of causal framework is in place, it becomes possible for machines to ask counterfactual questions—to inquire how the causal relationships would change given some kind of intervention—which Pearl views as the cornerstone of scientific thought. Pearl also proposes a formal language in which to make this kind of thinking possible—a 21st-century version of the Bayesian framework that allowed machines to think probabilistically.

Pearl expects that causal reasoning could provide machines with human-level intelligence. They’d be able to communicate with humans more effectively and even, he explains, achieve status as moral entities with a capacity for free will—and for evil. Quanta Magazine sat down with Pearl at a recent conference in San Diego and later held a follow-up interview with him by phone. An edited and condensed version of those conversations follows.

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We asked the experts to answer questions about all the places coronavirus lurks (or doesn’t). You’ll feel better after reading this.

When we asked readers to send their questions about coronavirus, a common theme emerged: Many people are fearful about tracking the virus into their homes on their clothes, their shoes, the mail and even the newspaper.

We reached out to infectious disease experts, aerosol scientists and microbiologists to answer reader questions about the risks of coming into contact with the virus during essential trips outside and from deliveries. While we still need to take precautions, their answers were reassuring.

Should I change my clothes and shower when I come home from the grocery store?

For most of us who are practicing social distancing and making only occasional trips to the grocery store or pharmacy, experts agree that it’s not necessary to change clothes or take a shower when you return home. You should, however, always wash your hands. While it’s true that a sneeze or cough from an infected person can propel viral droplets and smaller particles through the air, most of them will drop to the ground.

Studies show that some small viral particles could float in the air for about half an hour, but they don’t swarm like gnats and are unlikely to collide with your clothes. “A droplet that is small enough to float in air for a while also is unlikely to deposit on clothing because of aerodynamics,” said Linsey Marr, an aerosol scientist at Virginia Tech. “The droplets are small enough that they’ll move in the air around your body and clothing.”

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“I would encourage anyone interested in understanding the Great Depression or mid-19th century Britain to turn to Steinbeck or Dickens,” says Joseph E. Stiglitz, whose book “People, Power, and Profits” will be out in paperback soon.

What books are on your nightstand?

Like everyone, I have a large and aspirational pile on my nightstand. In fact, my wife recently bought me a bigger nightstand so we’d have more room for the books I want to read. Right now I’ve got “A Moveable Feast,” by Ernest Hemingway, to remind me of Paris, which I fell even more in love with during my term teaching there. “The Ratline,” because the author, Philippe Sands, is married to my wife’s sister and he sent it to us. Jill Lepore’s “These Truths” and “The Light That Failed,” by Ivan Krastev and Stephen Holmes, because everywhere I go people are talking about those two books. Ian McEwan’s “The Cockroach,” because the person who runs the renowned bookstore in Schloss Elmau (Germany) thought I would like this Kafkaesque parable of Brexit, in which a cockroach becomes prime minister. A book that was on my nightstand, but I have since read, is Hannah Lillith Assadi’s beautiful “Sonora,” a novel about the Arizona desert, New York City and the coming-of-age of a young woman whose parents are Palestinian and Israeli Jewish.

What’s the last great book you read?

“The In-Between World of Vikram Lall,” by M. G. Vassanji, in which a corrupt official now in hiding in Canada looks back on his life and the independence movement in Kenya. Particularly unforgettable are his memories of young love and the student movement in Dar es Salaam. The book was especially meaningful to me because of the time I spent working in Kenya between 1969 and 1971.

Are there any classic novels that you only recently read for the first time?

Inspired by Carl Miller’s rock opera about the lives of the Brontës, I read “Wuthering Heights.” What a book about inequality, sexuality, class. Beautifully atmospheric, too.

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