Practical ends are achieved through the application of scientific principles.
When I asked an engineer how his remote control worked, just before Masterpiece Theatre last evening, all I wanted to know was how to turn the device on. His eyes lit up when he sensed that what I really wanted to know was every excruciating detail about the principles of operation – mechanical, electrical, and infrared.
Feigning interest, I made the mistake of nodding my head and this he took as a go ahead for a further in depth discussion about material science – plastics and metals strength, fatigue factors, and wear characteristics. To really drive home his points, he decided to disassemble the remote control to expose and speak to the major components of each subsystem contained therein.
As he addressed assembly time, I asked if perhaps he could show me the series of steps necessary to put the device back together so that I might watch my show. Unfortunately, he detected an opportunity to improve on the design of one of the many pieces now arranged in a geometric grid on the coffee table before us and disappeared into his workroom to obtain just the right tool for the job.
I never did find out how the remote control worked but did learn wherein his passions lay.