PEOPLE: Human-Machine Interface – Who or What Controls What or Whom?

Los Alamos World Futures Institute

• World Futures:  What Do We Need?

The human-machine interface controls communication between the human and the machine.  Historically, it was intended to allow the human to have full control over the machine within the physical aspects of the machine’s capabilities.  As a simple example, consider the control switch on an electric range or cook-top.  

There is a knob labeled High-Medium High-Medium-Medium Low-Low-Warm-Off, or maybe the numbers 10 through 0.  

The human selects a setting that turns on (or off) a burner or heat element on the range.  In response, the device (an element in the range) allows a controlled rate of electricity to flow to the heating element which converts the electrical energy into heat energy – broadly.  Sensors on the range (maybe) turn the flow of electricity on and off to approximately maintain the temperature of the heating element in a certain range.  

Does the user need to know the correlation of the temperature ranges (in degrees Fahrenheit or Celsius) to the values on the knob?  Probably not.  The user adjusts the knob based on the reaction of the food being cooked while the cook-top follows the user’s commands “exactly.”

This same type of interface is and was applicable to most human controlled devices until the introduction of the digital computer.  Human beings had “complete” control of the device through physical interaction. Planes, trains, automobiles and ships reacted based on human commands.  As the devices grew in complexity, various advances permitted automated responses of the device such as flight stability, but absolute human control remained constant.

Then came the computer.  The first personal computers came with very extensive documentation of the operating system to allow the human user almost complete control of the machine without pulling the plug.  And the user, if sufficiently competent, could retrain the machine.  Yes, the user had to learn about the inner workings of the machine, but extensive documentation was provided.  And for simple tasks, it was already programmed.  Then came the graphical interface and the insightful influence of Apple.

The real impact of the graphical interface was that it made it easier for the average user to communicate with the computer for the execution of standard tasks and eliminate the need to learn the computer language.  The graphical interface was, in effect, a human-machine translator.  

While this was good, the translator was designed by a designer of the interface.  It represented the designer’s interpretation of what users needed to do.  

For the limited capabilities of the machines at the time, even though designers did not always get it right, it was good.  It permitted a large audience of humans access to a useful tool.

Moving forward, the technology has advanced in accord with Moore’s Law as evidenced by the reliance of people on the smart phone.  Observe people with these devices.  The phone beeps, chirps, or whatever and the owner of the phone immediately responds. Response has become an absolute “necessity.”  

Of course, the smart phone can be told what to beep, chirp, or whatever for by the user, but the smart phone updates its operating system automatically.  

Concurrently, the time intervals between interruptions have grown smaller and smaller.  While this may not be as significant for the older generations, especially those who grew up with party lines, are the members of the younger generations already controlled by these devices?  And are they, in fact, dependent on them?

Today we hear about automobiles that drive themselves.  Get into the vehicle and say “Computer! Take me to 123 XYZ Street.”  The automobile starts up, admonishes you to buckle your seat belt, and initiates the journey.  Somewhere a designer created the rules and algorithms the automobile used to select the route.  Ironically, the designer controls the computer in the automobile that controls both the automobile and you.

Who controls the designer?  The machine itself?  The machine user? Or the machine mission?  As we move into the future, what must the human-machine interface do or do we let the machines control humanity?

The Los Alamos World Futures Institute web site is at Feedback, volunteers, and donations (501.c.3) are welcome.

If your prefer to email us, please use or

Previously published articles can be found at or