## Apr 2 On the progression of Ideas

Engineers and philosophers exist at opposite ends of an ever widening continuum of thought. The field of philosophy has as its focus the discussion of what is knowable, what can be perceived, and what it means for a thing to exist. Engineers are appliers of tested concrete scientific knowledge and tools upon the present material world. Mathematics forms the underlying bridge that lets ideas move from nebulous to tested to applied.

### Example: Momentum to Safety Belts

PHILOSOPHY: Galileo, studying bodies in space with his telescope,  posits that things tend to keep moving on their own if left undisturbed. He goes so far as to say that anything in the universe, both in heavens and on earth, has a quality of motion about it called inertia. This is a move of sheer bravado, stating that one can actually know anything about the heavens. It is also rather abstract, since most things on earth come to a halt soon after being pushed. (Friction was not then identified as force in its own right.) Indeed, forces were not yet identified as players upon the world. To say that there was something possessed by an object in motion opened the door for further discussion.

MATHEMATICS: Newton took Galileo's concept of inertia further. Using experimentation with weights and a peculiar mathematical process of his own invention (calculus) he developed his foundational three laws. The first is just a re-statement of Galileo's: Objects in motion tend to stay in motion unless acted upon by an external force. He quantified this statement by saying that a moving mass possesses a quantity called momentum, and that momentum is equal to the mass times the object's velocity.

He tightened the definition to say that, when two bodies interact in an otherwise isolated situation (as in two rocks in space) the total momentum going into the process is equal to the total momentum coming out of the process - that is to say that momentum is conserved. Newton's third law completes the picture of how forces are applied when separate objects interact. Simply put, for every action there is an equal and opposite reaction; If I pull against you, you pull against me, and that amount of pulling is the same.

Conservation of momentum allows us to accurately calculate things like the velocity and direction of a pool ball after it is struck by a cue ball. It also can predict how much force is required to hold a person in her car seat, should the car come to a sudden halt from a specified speed.

ENGINEERING: Three hundred years passed. Too many people are dying in automobile accidents. The problem is identified as having to do with how a car will suddenly stop, but its passengers tend to keep moving - generally right out through the front glass and onto whatever did the stopping. A neurologist Dr. Hunter Sheldon invented the retractible automotive safety belt in 1946 as a way to prevent some of the injuries he witnessed in his practice.

His belt involved a special metal buckle that was easy to fasten and remove, but stayed clasped with enough force during an impact. How much force? He was able to calculate the required thickness of the straps, strength of the retaining bolts, and requirements of the latch mechanism using Newton's laws! Once the physical requirements were known, he could prescribe the proper materials and sizes to meet the constraints. This is, by definition, an act of engineering.

The process that takes foundational thought to applied technology has played out countless times through modern history:

• The field of computer science began with the notion that mathematics deals with purely abstract symbols that can be pushed around without the need for human intelligence. Once that concept was realized, a machine could be theorized and analyzed from a mathematical standpoint, and eventually constructed.
• Economics developed from vague notions of money flow into carefully tuned controls on the FED.
• Thoughts about the nature of sight developed into optical principles which lead to telescopes, cameras, and optical sensors.
• Musings on the nature of warmth became thermodynamics and lead to the design of practical internal combustion engines that still power our vehicles.

We live in a time that is seeing some of our most fundamental existential thought imported into the world of engineering: Artificial intelligence has grown from concepts of the mind that have been built into mathematical constructs, and then mechanized on vast scales using supercomputing data centers. What was once considered purely the realm of pure thought is being quantitatively defined and then crafted into tools toward a purpose.

May you find good purpose for your ideas. May you consider how your actions can be applied to help others. May you proceed with an awareness of the power you wield when you move the soul of an idea into the embodiment of a physical thing.