My inner scientist has to point out that thunder isn’t electricity itself, but the compression wave caused by the thermal expansion of the air surrounding a lightning bolt, ergo, an effect. And light is invisible as well. Take a laser pointer, you can’t see the beam unless there’s smoke in it’s path, or the dot on a wall. The light itself doesn’t take on a property until it reflects (or refracts) off an object. The sun or most light sources radiate light in all directions, and the light directly striking our eyes takes on a property once it is registered by the cornea. But be it a blue, red or green beam of directed light, you can’t see the beam unless something’s in it’s path, once again you see the effect of the light. But to be fair, I think he means more so the fact that the Sun’s light brings life and warmth to the entire planet, that’s an effect that we can not see but is still clearly there.

… sorry I’m a passionate debater. I couldn’t let a minor quip (that is incorrect) distract from such a fantastic article.

Agreed, but your three examples are people of such unusual worth and ability that 99.99% of the population has no hope whatsoever of imitating them. For the vast majority of us, influence comes down to having good looks, wealth, or kowtowing to others’ shortcomings.

To world you might be a one person, but for one person you might be the world.

Personal influence has helped me many times in positive directions! Great post.