---
title: "The hard problem · Library · Simulation Hypothesis"
url: https://simulation-hypothesis.com/library/hard-problem
description: "The hard problem is the question of why and how physical processes give rise to experience at all."
license: https://creativecommons.org/licenses/by/4.0/
credit: "Ross Allan Dahl, Simulation Hypothesis (simulation-hypothesis.com)"
---

## Philosophy of mind

# The hard problem

Definition

The hard problem is the question of why and how physical processes give rise to experience at all. David Chalmers coined the name, to set it apart from the “easy” problems of explaining behaviour and function.

On this site

The Mind model dial measures the easy problems. The hard problem isn’t in the total, because nobody knows what it would take.

Role in the model

The Mind total covers the easy problems: perception, memory and behaviour. All of those can be computed in principle. The hard problem isn’t in the total, because nobody knows what it would take, if it takes anything. When the sandbox says a scenario “thinks”, it isn’t claiming the scenario feels.

Related

[Consciousness](https://simulation-hypothesis.com/library/consciousness)[Qualia](https://simulation-hypothesis.com/library/qualia)[Philosophical zombie](https://simulation-hypothesis.com/library/philosophical-zombie)

## The people behind the terms

14 short pages, one per thinker, each with its matching dial. See also the [reading list](https://simulation-hypothesis.com/reading).

[Plato’s cave](https://simulation-hypothesis.com/thinkers/plato)[Zhuangzi’s butterfly](https://simulation-hypothesis.com/thinkers/zhuangzi)[Vasubandhu’s dream](https://simulation-hypothesis.com/thinkers/vasubandhu)[Shankara’s māyā](https://simulation-hypothesis.com/thinkers/shankara)[al-Ghazali’s doubt](https://simulation-hypothesis.com/thinkers/ghazali)[Ibn Arabi’s imagination](https://simulation-hypothesis.com/thinkers/ibn-arabi)[Calderón’s life is a dream](https://simulation-hypothesis.com/thinkers/calderon)[Descartes’ demon](https://simulation-hypothesis.com/thinkers/descartes)[Berkeley’s perceiver](https://simulation-hypothesis.com/thinkers/berkeley)[Borges’ circular ruins](https://simulation-hypothesis.com/thinkers/borges)[Nozick’s experience machine](https://simulation-hypothesis.com/thinkers/nozick)[Putnam’s brain in a vat](https://simulation-hypothesis.com/thinkers/putnam)[Bostrom’s trilemma](https://simulation-hypothesis.com/thinkers/bostrom)[Chalmers: virtual worlds are real](https://simulation-hypothesis.com/thinkers/chalmers)