left to say (which was often), which was, “Yes, Professor.”
He lowered his voice to a growl that shook my nerves some, “So I'll ask again, is red the same as green?”
My mind felt a little dizzy. I did not wish to disappoint him or face another lecture.
“Um. No?”
“No? You sound unsure.”
“Yes?”
The Professor dragged his hands across his face, “Is it yes or no? Be observant! Make an observation!”
I breathed deeply, “No. Red is not the same as green.”
“It isn't?”
“No.”
“Are you certain this time?”
“Yes.”
“Good. That was my conclusion as well. I see red, I see green, and I see that they are not the same. So let us play a little game.”
He took out a ruler from his pocket and handed it to me along with a pencil.
“Please mark, on the paper there, where red ends and where green begins.”
“But, um, there are other colours in between.”
“Then mark them out, also.”
Clumsily I drew on the page a line, just after the sheen of red turned to an orange. I measured a little across and drew another line between orange and yellow, then between yellow and green.
“You've marked this area as being distinct from this area, and this from this and so on,” he said, taking the pencil from me and pointing to the portions, “And this appears to be a valid separation, for this red here is clearly different from this orange, and this yellow likewise. Now, move the paper to the next bench please.”
“Further away?”
“Yes, just onto the next bench there. Note that the further the prism is from the paper, the greater the spread of the colours. This is to be expected.”
“I should suppose,” I replied, coming back to the professor, but he stopped me.
“No, stay there. I want you to do the same as before.”
“But it's too wide, now. The green has fairly moved off the paper.”
“That's quite alright. Just mark out the individual areas as best you can.”
I scratched my head and began again, this time getting up to yellow before going back on my work. The larger distance and greater separation of colours showed that there was something else afoot.
“It might be wise, to play this properly, to indicate that there are actually differences in colour between the orange and the red, and the orange and the yellow,” I muttered.
The Professor merely grinned, showing his teeth over his goatee beard, “And this is where our game becomes difficult. Where, pray, does the red stop being red?”
“Around about here, I should think. It's more of an orangey kind of...”
“Around about? Use the ruler, man! Draw a line! Surely red is red only up to a point?”
“Well, um, then there,” I said, making my mark, “But it's a little hazy. It's hard to make it distinct.”
“So it is. If it was easy, it wouldn't be much of a game. But that shows you yet another strange facet of light. Red is not red. Red is merely the name we give to the colour of light that is, as you said, around about there. Ish. Kind of. Sort of. Give or take,” he chuckled, “And that part you pointed out could easily, should I occlude this portion of the spectrum like so, it could easily pass as an orange.”
He held a card in front of the ray of light, blocking sections of the spectrum.
“I guess it could.”
“So, rather than a distinct separation of colours, one may conclude that the colours of the rainbow encompass a very gradual and subtle transition.”
“That is a revelation,” I said, looking closely at the rainbow, “I never thought of it like that.”
“Probably because you've not been taught to think of it like that. I could go on for some time about this topic, you know...”
“No doubt you could,” I mumbled, thinking about the long-winded lecture that morning.
“...for there are many, many interesting attractions to this field of optics. One, for example, is that when passing white light through particular media, we find that voids within the spectrum are produced.”
“I'm sorry?”
“Voids. Missing colours. Colours that otherwise would be there, but are strangely diminished in their intensity. It's a conundrum, one that I hope to examine when I've time, and one that is currently being scrutinised by some of my contemporaries.”
I pondered, “Why not join them?”
“I would, I would. But currently they are looking at merely reproducing what can be reproduced, and measuring what can be measured. It's a rather tedious part of study. I think that I shall be more content to examine what evidences they've gathered,” he said.
“But that might preclude you from discovering something important along the way.”
His eyebrows dropped and his chin jutted forward, thrusting his beard at me, “I don't do this for accolades, lad! It's for the betterment of understanding! It's for knowledge! My pride has no place in the history books, and it won't help any formulas to be derived.”
“My apologies. It's just that...”
“Every other scientist you've come across is hell-bent on being the next, great Pascal, the next Bernoulli?”
I reluctantly nodded, “Yes, in fact. I would not have put it so bluntly, but.”
“I know it. They have glorious visions of having their minds celebrated, thrust into the sky for all to admire. They revel in the gasps of wonder at their achievements, listen intently for their name being tied to a phenomenon, or a formula, or a method. And, while I'm not about to deny that such an honour would be most appreciated on my part, it would be only as a bonus to what reward I should receive upon discovering that vital piece of evidence, that delicious nugget upon which I can deliberate with my peers and bring the field away from the occult and into the light of science,” he intoned, his eyes sparkling softly in the lamplight, “And that is why I would like you to understand first what it is that you are looking for.”
“I see.”
“Or, rather, you don't!”
“But...”
“No, no. There is one last little portion of this game that I wish for you to play. The next step is only natural in the sequence that we've, so far, played out. Mark, with your graphite upon the paper, the point where you can no longer see any red light,” he instructed.
Carefully I took my ruler and drew a line where I determined that the redness was no longer visible. Again, it was a little unclear, but I was determined to mark it where there was not an speck of light showing.
“Good. That will do just fine. You've seen, then, that the light is dispersed across the paper, from red, through green, through cyans and blues, up through to violet. And, although it may appear obvious to you, we can see nothing further past that violet there, and nothing further past red in the other direction,” he summarised, quickly opening the blinds.
The sudden brightness caused me to squint. I could not tell if the Professor was doing the same, for he had donned a pair of shining, obsidian glasses.
“And so having established this clear set of rules, we need to ask ourselves if there is anything outside of the visible spectrum? Anything past the end lines that you have made?”
“I, um, I should think so.”
“But you cannot see it.”
“No,” I admitted plainly, “I can't...”
“Can you smell it? Go on, have a sniff. Can you feel it? If the answer is no, how can you form an opinion?”
I held my hands up, “Because you have already said that there is this infernal red!”
“Infra red, lad! That's right, though. I've already given you the answer. But, as a true scientist, you will want evidences for yourself, and I would think it only proper to demonstrate these to you. However, I fear we do not have as much time as all that, for I mean to get you into training...”
I started, “Training?”
“... immediately. And for this
I will require you to accept, at my word, that the spectrum continues unabated to the left and to the right, before the red and after the violet.”
“I have no objection to take this at face value.”
“You should!”
“What? But I don't! I'll be happy to question it, if you like.”
“No! Not if I like, it should – look, the necessity to question is a fundamental quality of a scientist! I was hoping for a bit more resistance...”
I shot, perhaps a bit too cheekily, “You were hoping to give another lecture!”
He harrumphed, “Quite! Quite! Another lecture indeed!”
“I mean no offence, Professor.”
“Yes, well, ahem, had you doubted me, I could have cited many experiments that point to the contrary and, I shall yield, I would be proud to demonstrate them for you. Well, take it as you like, but I expect that, as a friend and fellow you will question me more on this topic later!”
I nodded, happy to have one over the Professor, “I will. Thoroughly. But about this training.”
“Ah, yes. The training. You see, in order to test my theories of the effect of light upon the subjects, I need first to ensure that I can readily and repeatedly gain access to a subject.”
“A subject? You mean a ghost?”
“Call it what you will.”
“But how...”
“Can I conjure up a ghost? I cannot. But what I can do is use the power of statistical analysis to show me when a ghost is more likely to be manifest.”
“Yes, Professor.”
“Imagine, if you will, that I might perform such a similar experiment as that with the prism, at the drop of a hat, on demand, just like that,” he said, clicking his fingers, “Whenever I should please. That's repeatability. That's why I need successive encounters: so