---
title: Existence
date: 2012-05-04
techne: :wip
episteme: :speculation
---

So what's the deal with existence?

I don't get "things".[^things] Worse, I don't get "things exist" either.

Let's start with one version in which "exists" seems to make sense - the constructive one.

It's used as a technical term: "there exists an X, such that" (∃X: ...). You start with a precisely defined set of things (or rather, some constraints on thing-space), and then you ask questions about the cardinality of this set. If it's empty, no thing "exists" that fulfills the constraints that define the set. To say, "there exists an X, such that C" simply means, if I apply the constraints C to thing-space, I'll have at least one referent.

Or in other words, applying the rules C (the algorithm C) gives you a thing X, or fails to do so (either by returning nothing, or never halting). If it succeeds, X exists.

Existence, in that sense, is constraint-dependent. It makes no sense to ask if X exists "in general". The predicate of existence is always connected to a "such that". However, one might kind of generalize the predicate by observing that for any X, merely *naming* it gives a construction. Whatever you can think of *always* is the member of some set, and so "every thing" (everything you could name[^name]) "exists", in this sense.

[^name]: But remember that naming something [isn't trivial][Remark about Finitism].

One important feature of this view is how it treats "real" and "hypothetical" things.

Drawn from different sets.

If you have a construction, and that construction yields a thing, that thing exists. In other words, a "thing" is "what a construction does, assuming it doesn't fail". There's no "independent" existence of anything.

Nothing more can be said about things except their constraints, like whether they are "real" or "hypothetical" or anything like that. You can introduce the *construction* "is real", defined according to some rules, and then *according to this construction*, something may exist that is real.

But that's not an inherent property of the thing, but the result of performing some construction. Same for "hypothetical". Or "moral". Or "person".

You must already start with s


[^things]:
    What's "a thing"?

    "A number between 3 and 5 exists. Proof: 4." But what's "4"? I mean, I've never seen a "4". I've thought something that I think is the thought "4", but I'm not sure. What does "4" do? Maybe it makes more sense to translate everything to predicates, "to four"?

    The cleverest attempt I've seen to solve this is [Laws of Form][], which starts with the best commandment ever:

    1. Draw a distinction.

    It then introduces a name ("the mark") for everything *in* the distinction, and derives Boolean algebra and so on from that. (Similar approaches exist in Set Theory and elsewhere, of course, but I find Laws of Form the most beautiful.)
    
    I'm fine with the whole thing, except, you know, the first step. What's a "distinction"?
    
    I've never seen one, either. "Experience this, not that" doesn't work. I can only experience "this". I've never experienced not experiencing something.

    Si nemo ex me quaerat, scio; si quaerenti explicare uelim, nescio.
