“Let’s say the police get a report that a child has been abducted. Police detectives are trained to recognize patterns so they would know that the perpetrator is probably male and probably someone known by the child. And they could predict that the child is dead if missing more than forty– eight hours, with the body probably left outdoors within fifty miles of the crime. Let’s say the police call in an FBI profiler who is even more proficient than the police at spotting criminal patterns. Based on experience and statistics with similar crimes, the profiler might predict that the perpetrator has a certain type of background, upbringing, and personality. The police detectives and the FBI profiler can produce information that would seem psychic if you didn’t know it was based on simple patterns. Now let’s say the police contact a so-called psychic who is a genius at pattern recognition. At the genius level, far more subtle patterns come into play.”

He continued. “For example, the entertainment and news media create patterns in the public’s minds. Let’s say that several movies and TV shows about kidnappings in the past year have created a pattern about the best place to dispose of dead bodies. That pattern could influence a perpetrator to pick a drainage ditch instead of an old shack. The psychic unknowingly picks up on the pattern and ‘feels’ that the child will be found in a drainage ditch. A search of drainage ditches proves the psychic right.

“In such a case, the so-called psychic’s powers would be useful and in some sense genuine, but they could never be reproduced under controlled experiments. In a lab setting, all patterns are removed.”

“What about a guy who talks to your dead relatives?” I asked. “He always has information about the survivors and about the dead person that couldn’t be a coincidence. How’s that done?”

“That, too, is pattern recognition, along with showmanship, and sometimes trickery. Some of what passes as extraordinary psychic ability is nothing but playing the odds. The psychic might say, for example, that the deceased husband saw the widow kissing his picture. That would be a safe guess. Most widows kiss pictures of their dead husbands. Or the psychic might say that the departed husband liked to work with his hands at home. That applies to almost all men.

“The psychic can pick up many patterns suggested from a person’s voice, accent, clothes, age, name, health, and ethnicity. Let’s say a client has smoke-stained teeth. Smokers are likely to live with other smokers. The psychic might guess that a loved one recently died from heart or lung problems. That would be a good guess.”

“Okay, what about those televangelists who heal people on TV? Those people look healed to me. Is that fake?”

The old man just laughed. I laughed too.

“Consider light,” the old man said. “Our world appears infused with light’s energy. But what is light?”

“It’s made of photons,” I said, thinking that was a start. By then I should have known better. I think he ignored my answer.

“If you were in a spaceship racing a beam of light, and you were moving at ninety-nine percent the speed of light, how much faster would the light be?”

“About one percent of the speed of light, obviously. I don’t know the miles per hour.”

“Not according to Einstein. He proved that the light beam would be faster than your rocket ship by the speed of light, no matter how fast you are traveling.”

“That doesn’t make any sense. But it sounds vaguely familiar. Did he really say that?”

“Yes, and it is accepted as fact in the physics world.”

“That’s ridiculous,” I said. “If I’m traveling ninety-nine percent as fast as the light beam, in the same direction as the light, the light beam can’t be faster than me by the same speed as if I weren’t moving at all.”

“It’s ridiculous indeed. But scientists claim it is proven.”

“What if two rocket ships were racing the light beam and one was ninety-nine percent as fast as light and the other was fifty percent as fast? The light can’t be faster than both of them by exactly the speed of light.”

“And yet it would be.”

“Okay, that’s just plain crazy,” I replied. “You see, the light beam should be speeding away from the slower ship faster than it would be pulling away from the fast ship. That’s common sense.”

“It’s common and it’s wrong, according to scientific tests,” he argued. “It turns out that time and motion and the speed of light are different for all observers. We don’t notice it in daily life because the difference is very slight for slow-moving objects. But as you approach the speed of light, the differences become evident.

“It is literally true that no two people share the same reality. Einstein proved that reality is not one fixed state. Instead, it is an infinite number of unique realities, depending on where you are and how fast you are moving.

“If I were a passenger in the slow rocket ship that you used in your example, I would observe you pulling away from me at high speed. But from the perspective of the light beam, neither of us is moving at all. Both versions of reality are verifiably true, yet they are absurd when considered together.”

“So what the heck is light?” I asked.

“Light is the outer limit of what is possible. It is not a physical thing; it is a boundary. Scientists agree that light has no mass. By analogy, think of earth’s horizon. The horizon is not a physical thing. It is a concept. If you tried to put some horizon in a bucket, you couldn’t do it.

“Yet the horizon is observable and understandable. It seems to be physical and it seems to have form and substance. But when you run toward the horizon, no matter how fast you go, it seems to stay ahead of you by the same distance. You can never reach the horizon, no matter how fast you move.”

He continued. “Light is analogous to the horizon. It is a boundary that gives the illusion of being a physical thing. Like the horizon, it appears to move away from you at a constant speed no matter how fast you are moving. We observe things that we believe are light, like the searchlight in the night sky, the cloud-red sunset. But those things are not light; they are merely boundaries between different probabilities.

“Consider two plants. One is in direct light and the other is in perpetual shadow. The lighted plant experiences more possibilities because it lives longer and grows bigger and stronger. Eventually it will die, but not before it experiences many more possibilities than its shaded counterpart.”

“Okay,” I said, “I’m having trouble imagining light as not being a physical thing. How can it influence physical things if it isn’t physical itself?”

“There are plenty of nonphysical things that affect the world,” he said. “Gravity is not physical, and yet it seems to keep you from floating off the Earth. Probability is not physical, but it influences a coin toss anywhere in the universe. An idea is not physical and it can change civilization.”

“I don’t think ideas are an example of something nonphysical changing civilization. The brains of the people involved are physical things, and they influence our bodies, which are physical. I don’t see how ideas really enter into it, except in the way we label things. Ideas don’t float around in space by themselves. They’re always associated with something physical in our brains.”

“Suppose I write a hurtful insult on a piece of paper and hand it to you,” he replied. “The note is physical, but when you look at it, the information enters your mind over a pathway of light. Remember that light has no mass. Like magnetic fields, light exists in no physical form. When the insult on the note travels across the light path from the note to your eyes it is completely nonphysical for the duration of the trip. The insult encoded in the light is no more real than a horizon. It is a pure transfer of probability from me to you. When the insult registers in your mind, physical things start to happen. You might get angry and your neck and forehead might get hot. You might even punch me. Light is the messenger of probability, but neither the light nor the message has mass.