Quick! A laser is a beam of coherent light, but what does the name itself stand for?
Answer: Light Amplification by Stimulated Emission of Radiation (mouse-over)
Lasers can zap skin discolorations, whiten teeth and read the bar-codes on your groceries. They can
cut through steel.
Medical applications and
industrial processes aside, lasers are awesome, and while waiting for light-sabers to become available, one has to understand that a laser's real power lies not just in the pretty lights it produces, but in the principle that makes it work:
coherence. Lasers are
coherent light. Flashlights can't cut through anything but shadows, after all.
So what does it mean for something to be coherent, to possess coherence? A lot of terms get tossed around in the resulting scramble: "possessing internal consistency,
a : systematic or logical connection or consistency , b : integration of diverse elements, relationships, or values..."Possessing coherence in communication for example, is having orderly, logical sub-ideas radiating from a central idea. If you've ever had to go through outlining an essay in English class, it's like that. Try thinking of yourself as a spider -- an intelligence in the center of a web created of interlocking and related ideas. Even as the real spiders can spin webs of simply remarkable beauty where each connection made just so, coherence can make the connections between ideas beautiful in their clarity.
It's the difference between a labyrinth and a spider web. You don't get lost visually when looking at a spider web. When this happens, wherever you end up,
you can just latch on one idea that radiates from the center and use it to get back to the heart of the entire web.
Coherence gets to the point. Coherence radiates from the core.