Epistemology and Running
This is a lighthearted exploration of a theory developed with my friend Jared and my brother Sam while running.
Interestingly, my brother and I tend to share almost identical intuitions, while Jared (despite many shared interests) often lands on the opposite side of philosophical questions. (Why siblings' intuitions align so closely is a topic for another day.) That tension turned out to be productive. Pushback from an opposing intuition is often the fastest way to refine ideas.
What follows is not meant to be taken too seriously. Just a fun, structured debate that emerged over a few runs.
Without further ado, here's the theory.
Definitions and Axioms
Definition (Experience)
Experience is the immediately given, first-person phenomenal occurrence whose existence is indubitable to the subject at the moment it occurs.
Axiom 1 (Certainty of Experience)
The occurrence of experience is certain to the subject.
This axiom follows directly from the definition of experience and is therefore analytic rather than empirical.
Clarification: Certainty here applies only to the occurrence of experience, not to its causes, interpretation, or correspondence with external reality.
Axiom 2 (Opacity of Other Experience)
No subject can be certain of the occurrence of experience in another entity, regardless of behavioral, structural, or functional similarity.
Clarification: This axiom makes no claim about whether other entities do or do not have experience; it asserts only that the subject cannot be certain of such experience.
Reality
Definition (Reality)
Reality is that which exists independently of any particular subject's experience and is, in principle, common to all subjects.
Experience is first-person and indubitable; reality is third-person and universal.
Clarification: Reality is not identical to experience, nor reducible to any single subject's perceptions, even though it is only accessed through experience.
Summary So Far
- A subject can be certain only of its own experience
- A subject cannot be certain that any other entity experiences at all
- Reality is defined as universal and mind-independent
- Therefore: Any claim about reality necessarily goes beyond what can be known with certainty.
Reality Space
Definition (Reality Space)
Reality Space is the set of all possible realities consistent with a subject's experience.
Clarification: Reality Space represents epistemic possibility, not ontological plurality. Only one reality (if any) is actual, but the subject cannot know which one it is.
Proposition
If a subject can be certain only of its own experience and cannot be certain of the experience of others, then no single, determinate reality can be known with certainty.
Therefore, rational reasoning must take place over a set of possible realities.
Possible Realities
A possible reality is a complete specification of:
- What entities exist
- Which entities (if any) experience
- The structure governing appearances and interactions
Key Structural Insight
Experience constrains Reality Space, but does not collapse it.
Epistemic Indifference
Key Consequence
No remaining reality is epistemically privileged over any other.
Principle (Indifference)
Given only experience E, and no further distinguishing information, all realities consistent with E are epistemically indistinguishable and therefore equally weighted.
("Equally weighted" here reflects epistemic indifference, not literal frequency or ontological plurality.)
Closing Thought
Under this view, knowledge does not advance by reaching certainty about reality, but by progressively ruling out regions of Reality Space. Experience narrows the field, but never collapses it to a single point. What remains is uncertainty, not as a failure, but as the natural condition of reasoning about a shared world from a single point of view.
And with that those long cold runs were over in no time :)