III. The View from Nowhere

Professor Quillibrace was standing in the middle of the Common Room.

Mr Blottisham was sitting in an armchair.

Miss Stray was watching them both.

"You are in my way," said Blottisham.

"I am aware of that."

"Why?"

"I am observing you."

"From where?"

"Here."

"Then you're not observing me properly."

Quillibrace looked at him.

"Why not?"

"Because you're standing in front of me."

"I can see you perfectly well."

"But you are interfering with the experiment."

"What experiment?"

"The observation."

Miss Stray smiled.

"Perhaps you should move."

Quillibrace moved two feet to the left.

"There."

Blottisham nodded.

"Much better."

Quillibrace sat down.

"What exactly have we established?"

"That an observer should not interfere with what is being observed."

"Excellent."

Blottisham looked pleased.

"That is the basis of scientific objectivity."

"Is it?"

"Of course."

"The observer stands outside the system."

"Yes."

"And observes what is happening."

"Yes."

"Without interfering."

"Exactly."

Quillibrace glanced at Miss Stray.

She was still watching them.

"And where," he asked, "does the observer stand?"

Blottisham pointed at the floor.

"Here."

"Then he is part of the world."

"That is irrelevant."

"Why?"

"Because he is observing it."

"From inside it."

"Yes."

"Without being part of it."

Blottisham hesitated.

"I don't think you can have it both ways."

Miss Stray spoke quietly.

"Perhaps that is the problem."

Blottisham looked at her.

"What problem?"

"The observer."

"What about the observer?"

"We keep imagining one."

"Well, there is one."

"You."

Blottisham pointed at Quillibrace.

"Him."

"Yes."

"Then what's the difficulty?"

Quillibrace leaned back.

"Perhaps we should begin with something simpler."

He picked up a teaspoon from the table.

"What is this?"

"A teaspoon."

"Does it exist when nobody is looking?"

"Obviously."

"Good."

"Why are you asking?"

"Because I want to know whether observation creates the spoon."

"It doesn't."

"Excellent."

He put the spoon down.

"Now suppose I measure the position of a particle."

"Yes."

"Is the measurement simply a matter of looking at where the particle already is?"

"Yes."

"How do you look?"

"With an instrument."

"Is the instrument physical?"

"Of course."

"Does the particle interact with it?"

"Presumably."

"Not presumably."

Quillibrace looked at him.

"Physically."

Blottisham nodded.

"Physically."

"So the measurement is an interaction between physical systems."

"Yes."

"The apparatus is part of the physical world."

"Yes."

"The particle is part of the physical world."

"Yes."

"And the interaction between them is part of the physical world."

"Yes."

Quillibrace paused.

"Then where is the observer?"

Blottisham frowned.

"Behind the apparatus."

"No."

"Beside it."

"No."

"Outside the laboratory."

"No."

"In his office."

"No."

"At home?"

"No."

Blottisham looked irritated.

"Then where?"

Miss Stray said:

"Perhaps nowhere."

There was a silence.

Blottisham stared at her.

"That's absurd."

"Is it?"

"An observer has to be somewhere."

"Exactly."

Quillibrace smiled.

"That is the difficulty."

Blottisham folded his arms.

"I think you're making this unnecessarily philosophical."

"On the contrary."

Quillibrace gestured towards the laboratory.

"The apparatus becomes correlated with the system."

"Yes."

"An outcome occurs."

"Yes."

"Something physical happens."

"Yes."

"So why do we need to imagine an additional observer standing outside the physical process?"

"Because someone has to know the result."

"No."

Blottisham blinked.

"No?"

"The detector can register it."

"But someone has to read the detector."

"Eventually."

"So eventually there is an observer."

"Yes."

"But that observer is another physical system."

Blottisham frowned.

"And then?"

"Then another interaction."

"With another observer?"

"Possibly."

"And another?"

"Possibly."

"And another?"

"Where would you stop?"

Blottisham looked annoyed.

"At the human mind."

"Why?"

"Because that's where observation really happens."

Miss Stray looked up.

"Why?"

"Because the mind is conscious."

"And what makes consciousness the boundary?"

"Because..."

Blottisham stopped.

Quillibrace waited.

"Because consciousness is where someone actually sees the result."

"Does a photographic plate see?"

"No."

"Does a detector see?"

"No."

"Does an animal see?"

"Yes."

"Does a computer see?"

"I don't know."

"Does a brain see?"

"Yes."

Quillibrace nodded.

"So the important thing is not seeing."

"What, then?"

"Physical interaction."

Blottisham looked at him.

"You've removed the observer."

"No."

"You've removed consciousness."

"No."

"Then what have you removed?"

"The need for a privileged observer."

Miss Stray smiled.

"That is rather different."

Blottisham sat back.

"I don't like it."

"I know."

"Without an observer, how do we know what happened?"

Quillibrace looked at him.

"How do you know the sun rose this morning?"

"I saw it."

"Did the sun rise because you saw it?"

"No."

"Then your seeing it was not what made it happen."

"No."

"Good."

"But quantum mechanics is different."

"Perhaps."

"Measurements matter."

"Yes."

"So the observer matters."

"Not necessarily in the sense you mean."

Blottisham frowned.

Miss Stray intervened.

"Perhaps the confusion is between two different ideas."

"Which are?"

"That observation is physically involved in an event, and that human consciousness creates the event."

Blottisham looked at her.

"Those aren't the same thing?"

"No."

Quillibrace nodded.

"A measuring apparatus can interact with a quantum system without anyone looking at the result."

"Yes."

"A photographic plate can record an event."

"Yes."

"A detector can register a particle."

"Yes."

"So consciousness is not required for physical interaction."

"No."

Blottisham thought for a moment.

"Then what does the observer do?"

"Participates."

"In what?"

"In an experimental arrangement."

Blottisham looked puzzled.

"But scientists are supposed to be objective."

"They are."

"So they shouldn't participate."

"Why not?"

"Because participation is subjective."

Quillibrace sighed.

"That is a remarkably persistent confusion."

Miss Stray smiled.

"Perhaps objectivity doesn't require detachment."

"What does it require?"

"That the world can resist you."

Blottisham looked at her.

She continued.

"You make a prediction."

"Yes."

"You perform an experiment."

"Yes."

"The result may surprise you."

"Yes."

"That surprise is not subjective."

"No."

"It is the world answering back."

Quillibrace nodded.

"Objectivity may therefore be reliable participation in relations that constrain what we can say."

Blottisham considered this.

"So I'm objective because the world can tell me I'm wrong."

"Precisely."

"I don't like that either."

"Science is full of disappointments."

Blottisham stood and walked to the window.

"Still," he said, "there is something uncomfortable about this."

"What?"

"The scientist is part of the world."

"Yes."

"The apparatus is part of the world."

"Yes."

"The measurement is part of the world."

"Yes."

"And then the scientist observes the measurement."

"Yes."

"So the world is observing itself."

Quillibrace looked at Miss Stray.

Miss Stray looked at the window.

"That," she said, "is one way of putting it."

Blottisham turned.

"That's rather grand."

"It is also rather ordinary."

"How can it be both?"

"Because there is no need for a privileged standpoint outside reality."

She paused.

"We are organisms in the world."

"Yes."

"We build instruments in the world."

"Yes."

"We interact with other things in the world."

"Yes."

"We construct theories about those interactions."

"Yes."

"And those theories change what we do next."

Blottisham slowly nodded.

"So knowledge is a feedback process."

"Exactly."

"The world affects us."

"Yes."

"We affect the world."

"Yes."

"We measure what happens."

"Yes."

"We interpret it."

"Yes."

"And then we do something else."

"Yes."

Blottisham looked thoughtful.

"That's rather less like looking through a window."

"Much less."

"And rather more like..."

He searched for the word.

"Participating."

"Yes."

There was a pause.

Blottisham returned to his chair.

"But surely," he said, "we can still distinguish observer from observed."

"Certainly."

"So what's changed?"

"The distinction remains useful."

"Then why all this fuss?"

"Because useful distinctions need not be absolute divisions."

Miss Stray nodded.

"The detector can be the observer in one experiment and the observed system in another."

"The scientist can be the observer."

"Yes."

"And the scientist can be the observed system."

"Yes."

Blottisham looked alarmed.

"By whom?"

Quillibrace smiled.

"That is the interesting question."

Blottisham thought about this.

"So there is no absolute observer."

"No."

"No privileged position."

"No."

"No view from outside."

"No."

"Then how can we observe the universe?"

Quillibrace looked at him.

"We don't."

Blottisham stared.

"We observe from within it."

Miss Stray said quietly:

"We know the world from within the world."

The three of them were silent.

Outside, a lawnmower started.

Blottisham looked towards the window.

"That's rather noisy."

"Indeed."

"Can we observe it without interfering?"

Quillibrace looked at him.

"It has already interfered with us."

Blottisham nodded.

"I suppose it has."

He picked up his tea.

"And yet," he said, "I still feel there ought to be somewhere from which one could see the whole thing."

"Where?"

Blottisham thought.

"Somewhere outside."

"Outside what?"

"The universe."

Quillibrace waited.

Blottisham's expression slowly changed.

"Ah."

Miss Stray smiled.

"Yes."

He sat down again.

"That's impossible."

"Conceptually."

"Physically?"

"Also."

Blottisham sighed.

"So there is no view from nowhere."

"No."

"That's disappointing."

"Only if you wanted to observe the universe without being part of it."

Blottisham considered this.

"Which I did."

"Naturally."

A silence followed.

Then Blottisham looked up.

"Professor?"

"Yes?"

"If we're all part of the process..."

"Yes?"

"...what happens to the future?"

Quillibrace looked at Miss Stray.

She was already looking at him.

"The future," she said, "may be the next problem."

Quillibrace picked up his book.

"Yes."

Blottisham looked pleased.

"Good."

"Why?"

"Because I was beginning to think we had finished."

"We have."

"Already?"

"With this problem."

Blottisham nodded.

"And the next one?"

Quillibrace opened his book.

"Unfortunately, it has already begun."