The Reality Principle

By Monty Reynolds in Modal Worlds David Lewis

January 2, 2021

Hi, I'm the here-bot cat!

Use me to find your way in your website.

Here I am:
content/blog/lewis-series/02-spoonful/index.md

To remove me, delete this line inside that file: {{< here >}}

My content section is:
blog
My layout is:
single-series
Images in this page bundle:
/blog/lewis-series/02-spoonful/sidebar-inverse.jpg

If $$p_{1}, . . . p_{n}$$ are the propositions whose fictionality a representation generates directly, another proposition, q, is fictional in it if, and only if, were it the case that $$p_{1}, . . . p_{n}$$, it would be the case that q.

$$\frac{\psi^{1}, . . ., \psi^{n}}{\therefore\phi}$$

Where there is a wn between w1-n at which $$\neg\psi\land\phi$$

You might think that there is no reason to think that Sherlock Holmes has 105 number of hairs on his head anywhere in the set $$\psi_{1-n}$$ but if this is true, then it does not answer those cases where:

  • Holmes lived on Baker Street (which is not nearer Paddington Station than it is Waterloo Station in the actual world w0)
  • Holmes lived nearer to Paddington Station than Waterloo Station
  • Holmes was just a person—a person of flesh and blood (Not person of flesh and blood at w0)
  • Holmes really existed (doesn’t exist?)

The interpreter of the fiction is to ask: “what the real world would be like if the propositions (as a whole within fiction) whose fictionality is generated directly were true: What else would be true if they were?”

We can possibly amend this problem by prefixing an operator; say “In the fiction f . . .”, to each premiss and to the conclusion of the original arguments.

$$\frac{In f, \psi^{1}, . . ., In f, \psi^{n}}{\therefore In f, \phi}$$