The Future of Computers Is the Mind of a Toddler
Facebook and Google are
trying to create artificial intelligence that mimics the human brain.
First, they need to figure out how our own minds work
June 9, 2015
by Jack
Clark
Photographer:
Adrian Lourie/Evening Standard/Redux
Machines contain the breadth of human knowledge,
yet they have the common sense of a newborn. The problem is
that computers don't act enough like toddlers. Yann LeCun,
director of artificial intelligence research at Facebook,
demonstrates this by standing a pen on the table and then
holding his phone in front of it. He performs a sleight of hand, and
when he picks the phone up—ta-da! The pen is gone. It’s a trick
that’ll elicit a gasp from any one-year-old child, but today's
cutting-edge artificial intelligence software—and most
months-old babies—can’t appreciate that the disappearing act
isn’t normal. “Before they’re a few months old, you play this
trick on them, and they don’t care,” says LeCun, a 54-year-old
father of three. “After a few months, they figure out this is not
normal.”
One reason to love computers is that, unlike
many kids, they do as they’re told. Just about everything a
computer is capable of was put there by a person, and they've
rarely been able to discover new techniques or learn on their
own. Instead, computers rely on scenarios created by software
programmers: If this happens, then do that. Unless it's explicitly
told that pens aren't supposed to disappear into thin air, a computer
just goes with it. The big piece missing in the crusade for
the thinking machine is to give computers a memory that works like
the grey gunk in our own heads. An AI with something resembling brain
memory would be able to discern the highlights of what it sees, and
use the information to shape its understanding of things over
time. To do that, the world's top researchers are rethinking how
machines store information, and they're turning to neuroscience
for inspiration.
This change in thinking has spurred an AI
arms race among technology companies such as Facebook, Google, and
China’s Baidu. They’re spending billions of dollars to
create machines that may one day possess common sense and to help
create software that responds more naturally to users’ requests and
requires less hand-holding. A facsimile of biological memory, the
theory goes, should let AI not only spot patterns in the
world, but reason about them with the logic we associate with young
children. They’re doing this by pairing brain-aping bits of
software, known as neural networks, with the ability to store
longer sequences of information, inspired by the long-term memory
component of our brain called the hippocampus. This combination
allows for an implicit understanding of the world to get “fried in”
to the patterns computers detect from moment to moment, says
Jason Weston, an AI researcher at Facebook. On June 9, Facebook plans
to publish a research
paper detailing a system that can chew through several
million pieces of data, remember the key points, and answer
complicated questions about them. A system like this might let a
person one day ask Facebook to find photos of themselves wearing
pink at a friend's birthday party, or ask broader, fuzzier questions,
like whether they seemed happier than usual last year, or
appeared to spend more time with friends.
While AI has long been an area of interest for
Hollywood and novelists, companies hadn't paid much attention to it
until about five years ago. That's when research institutions and
academics, aided by new techniques for crunching reams of data,
started breaking records in speech recognition and image analysis at
an unexpected rate. Venture capitalists took
notice and invested $309.2 million in AI startups
last year, a twentyfold increase from 2010, according to
research firm CB Insights. Some of these startups are helping to
break new ground. One in Silicon Valley, called MetaMind, has
developed improvements to computers' understanding of everyday
speech. Clarifai, an AI startup in New York, is doing complex video
analysis and selling the service to businesses.
Corporate research labs now rival those in
academia in terms of staffing and funding. They have surpassed them
in access to proprietary data and computing power to run experiments
on. That's attracting some of the field's most prominent
researchers. LeCun, former director of New York University's Center
for Data Science, joined Facebook in December 2013 to run its AI
group. While still teaching a day a week at NYU, he has hired nearly
50 researchers; on June 2, Facebook said it is opening an AI lab
in Paris, its third such facility. Google says its own AI team
numbers in the “hundreds,” declining to be more specific. Baidu's
Silicon Valley AI lab opened in May 2014, and now has
around 25 researchers led by Andrew Ng, a former AI head at Google.
The Chinese search giant employs about 200 AI
specialists globally. The interest from deep-pocketed consumer
Internet companies kickstarted a research boom creating “one of the
biggest advances” in decades, says Bruno Olshausen, head of the
Redwood Center for Theoretical Neuroscience at the University of
California-Berkeley. “The work going on in these labs is
unprecedented in the novelty of the research, the pioneering aspect.”
As far as tech money has pushed AI in recent
years, computers are still pretty dumb. When talking to friends in a
loud bar, you pick up what they're saying, based on context and what
you remember about their interests, even if you can't hear every
word. Computers can't do that. “Memory is central to cognition,”
says Olshausen. The human brain doesn't store a complete log of each
day's events; it compiles a summation and bubbles up the highlights
when relevant, he says. Or at least, that's what scientists think.
The problem with trying to create AI in our own image is that we
don't fully comprehend how our minds work. “From a neuroscience
perspective, where we are in terms of our understanding of the
brain—and what it takes to build an intelligent system—is kind of
pre-Newton,” Olshausen says. “If you're in physics and
pre-Newtonian, you're not even close to building a rocket ship.”
Modern AI systems analyze images, transcribe
texts, and translate languages using a system called neural networks,
inspired by the brain's neocortex. Over the past year,
virtually the entire AI community has begun shifting to a
new approach to solve tough-to-crack problems: adding a memory
component to the neuron jumble. Each company uses a different
technique to accomplish this, but they share the same emphasis
on memory. The speed of this change has taken some experts
by surprise. “Just a few months ago, we thought we were the only
people doing something a bit like that," says Weston, who
co-authored Facebook's first major journal article about memory-based
AI last fall. Days later, a similar paper appeared from
researchers at Google DeepMind.
Since then, AI equipped with a sort of short-term
memory has helped Google set records in video and image analysis, as
well as create a machine that can figure out how to
play video games without instructions. (They share more in
common with kids than you probably thought.) Baidu has also made
significant strides in image and speech recognition,
including answering
questions about images, such as, “What is in the center of the
hand?” IBM says its Watson system can interpret
conversations with an impressive 8 percent error rate.
With Facebook's ongoing work on memory-based AI software that
can read articles and then intelligently answer questions about their
content, the social networking giant aims to create “a
computer that can talk to you,” says Weston. The next step is to
create an accompanying framework more akin to long-term memory,
which could lead to machines capable of reasoning, he explains.
If a talking, learning, thinking machine sounds a
little terrifying to you, you're not alone. “With artificial
intelligence, we're summoning the demon,” Elon Musk said last
year. The chief executive officer of Tesla Motors has a
team working on AI that will let its electric cars drive themselves.
Musk is also an investor in an AI startup named Vicarious.
After some apparent self-reflection, Musk
donated $10 million to the Future of Life Institute, an
organization set up by Massachusetts Institute of Technology
Professor Max Tegmark and his wife Meia to spur discussions about
the possibilities and risks associated with AI. The organization
brings together the world's top academics, researchers, and
experts in economics, law, ethics, and AI to discuss how to develop
brainy computers that will give us a future bearing more resemblance
to The Jetsons than to Terminator.
“Little serious research has been devoted to the issues, outside of
a few small nonprofit institutes. Fortunately, this is now changing,”
Stephen Hawking, who serves on the institute's advisory board, said
at a Google event in May. “The healthy culture of risk assessment
and the awareness of societal implications is beginning to take root
in the AI community.”
AI teams from competing companies are working
together to advance research, with an eye toward doing so in
a responsible way. The field still operates with an academic
fervor reminiscent of the early days of the semiconductor
industry—sharing ideas, collaborating on experiments, and
publishing peer-reviewed papers. Google and Facebook are
developing parallel research schemes focused on memory-based AI,
and they're publishing their papers to free academic repositories.
Google's cutting-edge Neural Turing Machine “can learn really
complicated programs” without direction and can operate them pretty
well, Peter Norvig, a director of research at Google, said in a
talk in March. Like a cubicle dweller wrestling with Excel, the
machine makes occasional mistakes. And that's all right, says Norvig.
“It's like a dog that walks on its rear legs. Can you do it at all?
That's the exciting thing.”
Technological progress within corporate AI
labs has begun to make its way back to universities.
Students at Stanford
University and other schools have built versions of Google's
AI systems and published the source code online for anyone to use or
modify. Facebook is fielding similar interest from academics. Weston
delivered a lecture at Stanford on May 11 to more than 70
attending students—with many more tuning in online—who were
interested in learning more about Facebook's Memory Networks project.
LeCun, the Facebook AI boss, says, “We see ourselves as not
having a monopoly on good ideas.” LeCun co-wrote a paper
in the science journal Nature on May 28, along
with Google's Geoff Hinton and University of Montreal Professor
Yoshua Bengio, saying memory systems are key to giving computers the
ability to reason about the world by adjusting their understanding as
they see things change over time.
To illustrate how people use memory to respond to
an event, LeCun grabs his magic pen from earlier and tosses it at
a colleague. A machine without a memory or an understanding of
time doesn't know how to predict where an object will land or how to
respond to it. People, on the other hand, use memory and common sense
to almost instinctively catch or get out of the way of what's coming
at them. Weston, the Facebook AI researcher, watches
the pen arc through the air and then hit him in the arm. “He's
terrible at catching stuff,” LeCun says, with a laugh, “but
he can predict!” Weston reassures him: “I knew it was going to
hit me.”
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