Humanity vs. A Computer

In February 2011 human brainpower faced off against Watson, IBM’s supercomputer, in a battle of knowledge and processing speed on the popular TV show Jeopardy. Who would win? Ken Jennings and Brad Rutter, the top two all-time Jeopardy winners, or Watson, IBM’s synthetic creation? After three intense matches, Watson had defeated the human competition. Watson’s win had some fearing that computers had finally advanced beyond the human brain. But, I say, not so fast—let’s do a little comparison between Watson and a human brain and see how well the human brain stands up.

Watson is composed of 90 IBM Power 750 servers, each 6.9 inches high, 17.3 inches wide, 28.7 inches deep and weighing 120 pounds, for a total weight of over 10,000 pounds—housed in 10 large racks in a room approximately 12 feet by 10 feet.1 Watson contains 2,880 Power7 processors, with each processor consisting of 8 cores containing 1.2 billion transistors and 16 terabytes of RAM,2 processing 500 gigabytes of information per sec (1 million books/sec).3

In comparison, the human brain weighs about 3 pounds and is contained within the small space inside the skull. The brain is estimated to have more than 100 billion nerve cells and over one trillion supporting cells. Each nerve cell can have up to 10 thousand connections to other nerve cells, which makes the brain highly interconnected with some estimates of over a quadrillion connections.

The human brain holds approximately 1.25 terabytes of data and performs at approximately 100 teraflops5 (one hundred trillion point operations per second). Watson holds 1 terabyte of data and performs at 80 teraflops (eighty trillion point operations per second).6

In addition to actually having greater speed and storage capacity than Watson, the human brain, being housed in the body, is highly portable and can choose to move itself from place to place; Watson cannot. The human brain can experience emotions; Watson cannot. The human brain can rewire itself based on new experience or a change in understanding; Watson cannot. The human brain can grow new components (neurons); Watson cannot. Ultimately, the human brain turns out to be the most marvelous piece of engineering known, far beyond human ingenuity and immeasurably more complex than Watson.

Then why did Watson win? According to Ken Jennings, it had nothing to do with knowledge or ability to answer the questions. It all came down to who could ring in fastest. Jennings said in an interview after the competition, “Jeopardy! devotees know that buzzer skill is crucial—games between humans are more often won by the fastest thumb than the fastest brain. This advantage is only magnified when one of the ‘thumbs’ is an electromagnetic solenoid triggered by a microsecond-precise jolt of current.