What does the word “understand” mean?.  From the outside, is it possible to know whether someone — or some AI program — “understands” you.  What does that even mean?  

I assert that if you “understand” something, then you should be able to answer questions and perform tasks based on your understanding. If there are multiple tasks, then there are multiple meanings of “understand”.  Consider this classic nursery rhyme:

Jack and Jill went up the hill
To fetch a pail of water
Jack fell down and broke his crown
And Jill came tumbling after

There are many different tasks an AI program can perform, leading to multiple different meanings of “understand”.  Different programs can perform different tasks: 

1. Return Counts: 4 lines, 25 words
   A simple procedural program can possess a very rudimentary understanding of the text.
2. Return Parts of speech: nouns: Jack, Jill, hill, … verbs: went, fell, broke
   Simple NLP processing can understand each word’s part of speech.
3. Return Translation: Jack und Jill gingen den Hügel hinauf …
   Translation between, say, English and German, requires more understanding of the text to ensure noun and verb agreement, how to properly reorder the words, etc. 
4. Return Summary: Story about boy and girl’s disaster while doing a daily task
   Summarization is a much harder task. 
5. Use Common sense: it’s odd they went uphill to get water
   It’s “just common sense” that you go down the hill to get water, not up the hill.  This is a very hard problem. 
6. Create Interpretation: Attempt by King Charles I to reform the taxes on liquid measures. He … ordered that the volume of a Jack (1/8 pint) be reduced, but the tax remained the same. … “Jill” (actually a “gill”, or 1/4 pint) is said to reflect that the gill dropped in volume as a consequence. [Wikipedia]
   I love this explanation about the nursery rhyme from WIkipedia: it was political condemnation, encoded as a poem, about King Charles’ attempt to raise tax revenue without changing the tax rate.  A program that could return explanations like this have an extremely deep understanding of the poem and its social and political context. 

Of course, we could add many other definitions/tasks to this list, each leading to a new definition for “understand”. As the list grows, some pairs of definitions can’t be ordered according to difficulty, so that list would not be totally ordered.

This highlights a major source of confusion.  A company whose software implements a simple task (high on this list) can correctly claim their software “understands”. But the lay public most often interprets “understand” to be a very complex task (low on the list). When this happens the company has “overhyped” or “oversold” their software.

The fundamental problem is some words, like “understand”, are just too vague.  Eskimos have over 50 words for different kinds of “snow”, each describing a particular shades of meaning. I assert we need more granular words for “understands” — and other similarly vague words — to represent the different shadings.

A good example of what I mean comes from the US National Highway Traffic Safety Administration (NHTSA). They define multiple capability levels for autonomous vehicles:

• Level 0: The driver (human) controls it all: steering, brakes, throttle, power.
• Level 1: Most functions are still controlled by the driver, but a specific function (like steering or accelerating) can be done automatically by the car.
• Level 2: at least one driver assistance system of “both steering and acceleration/deceleration using information about the driving environment” is automated, like cruise control and lane-centering. … The driver must still always be ready to take control of the vehicle.
• Level 3: Drivers are able to completely shift “safety-critical functions” to the vehicle, under certain traffic or environmental conditions. The driver is still present and will intervene if necessary, but is not required to monitor the situation in the same way it does for the previous levels.
• Level 4: “fully autonomous” vehicles are “designed to perform all safety-critical driving functions and monitor roadway conditions for an entire trip. However, … it does not cover every driving scenario.
• Level 5: fully-autonomous system that expects the vehicle’s performance to equal that of a human driver, in every driving scenario—including extreme environments like dirt roads that are unlikely to be navigated by driverless vehicles in the near future.

If a company claims they offer a “Level 3” car, the public will correctly know what to expect.

So the next time someone says “I understand”, give them a few tasks to see how deeply they really do “understand”.

What do you think?  Did you “understand” this post.  🙂