Eric Schwitzgebel                             about 3000 words

Department of Philosophy

U.C. Riverside

Riverside, CA  92521-0201

Eschwitz at domain-



Originally published in Sci Phi Journal, issue 3, 2015.  The version below is lightly revised as of April 21, 2017.











The Tyrant’s Headache


Preface: The parable below is intended as a critique of David Lewis’s essay “Mad Pain and Martian Pain” (1980), a classic and influential articulation and defense of a sophisticated form of functionalism about conscious experience.  According to Lewis’s functionalism, to be in a mental state is to be in a physical state that plays the right type of causal-functional role for normal members of the population to which you belong.  To be in pain, for example, on Lewis’s view, is to be in a brain state (or if you’re a hydraulic Martian, a hydraulic state) that, for normal members of your population, is typically caused by things like tissue damage and in turn typically causes avoidance and other aversive responses.

All block quotes are from Lewis’s essay.  I choose Lewis as the target of my parable, but similar worries arise for other prominent philosophical approaches to pain in philosophy of mind, including the approaches of Michael Tye (1997, 2005a&b) and Christopher Hill (2009).  All these approaches share a common problematic feature: According to them, pain depends not only on local features of the individual in pain but also on what is normal in the species or what was selected for in the evolutionary past of the species.  (To see this fully for Tye and Hill, it helps to know also their general views about the relationship between conscious experience and evolutionary history, e.g., in their treatments of “Swampman”: Tye 2000, ch. 6; Hill 2009, ch. 5.)  This parable explores the seemingly bizarre consequences of this class of views.




When the doctors couldn’t cure the Tyrant’s headache, he called upon the philosophers.  “Show me some necessary condition for having a headache, which I can defeat!”

The philosophers sent forth the great David K. Lewis in magician’s robes.  With him traveled a madman, in top hat and monocle, and a Martian.  Said the Philosopher to the Tyrant:

There might be a strange man who sometimes feels pain, just as we do, but whose pain differs greatly from ours in its causes and effects.  Our pain is typically caused by cuts, burns, pressure, and the like; his is caused by moderate exercise on an empty stomach.  Our pain is generally distracting; his turns his mind to mathematics, facilitating concentration on that but distracting him from anything else.  Intense pain has no tendency whatever to cause him to groan or writhe, but does cause him to cross his legs and snap his fingers.  He is not in the least motivated to prevent pain or to get rid of it.

The Philosopher gestured at the madman, who did forty jumping-jacks, then sat crosslegged upon a windowsill, snapped his fingers six times, and began a discourse on the relation between e and π.  (“Most Stoical, how he deals with his pain!” whispered an advisor to the Tyrant.)

Continued the Philosopher:

Also, there might be a Martian who sometimes feels pain, just as we do, but whose pain differs greatly from ours in its physical realization.  His hydraulic mind contains nothing like our neurons.  Rather, there are varying amounts of fluid in many inflatable cavities, and the inflation of any one of these cavities opens some valves and closes others.  His mental plumbing pervades most of his body – in fact, all but the heat exchanger inside his head.  When you pinch his skin, you cause no firing of C-fibers – he has none – but, rather, you cause the inflation of many smallish cavities in his feet.  When these cavities are inflated, he is in pain.  And the effects of pain are fitting: his thought and activity are disrupted, he groans and writhes, he is strongly motivated to stop you from pinching him and to see to it that you never do again.

The Philosopher gestured at the Martian, who gave the customary three-elbow salute, then dodged the Philosopher’s attempted pinch.

Continued the Philosopher:

As materialists, we want to characterize pain as a physical phenomenon.  We can speak of the place of pain in the causal network from stimuli to inner states to behavior.  And we can speak of the physical processes that go on when there is pain and that take their place in the causal network.  We seem to have no other resources but these.  But the lesson of mad pain is that pain is associated only contingently with causal role, while the lesson of Martian pain is that pain is connected only contingently with its physical realization.

“Oh, ’tis a puzzle most perplexing!” said the Tyrant to the Philosopher.  “My subjects may feel pain for diverse and bizarre reasons, as I have well discovered in my chambers, and they may react to it in strange and different ways, as I have also closely observed.  Some even appear to seek pain.”  Here, the Tyrant paused to gaze wisely across the sea, his eyes perhaps tilted slightly toward the heavens.  “So we cannot identify pain with any particular causal role.  Pain would instead seem to be a particular physiological state of the brain, which can be variously caused and various in its effects.  Who could deny it!  And yet, it would seem then to follow that no being with a differently constructed brain could feel pain, much less a being with no brain at all!”

The Royal Torturer now wrapped her net around the Martian and smiled gently.  The Martian whined and quailed.

Concluded the Tyrant: “This manifest absurdity and contradiction might indeed be the atypical cause of my unceasing pain!  What is a piece of flesh, that it might have a headache?  O, Philosopher, can you shatter me up this fearsome granite?”

Said the Philosopher:

The concept of pain... is the concept of a state that occupies a certain causal role, a state with certain typical causes and effects... for a population....  Human pain is the state that occupies the causal role of pain for humans.  Martian pain is the state that occupies the same role for Martians....  We may say that X is in pain... if and only if X is in the state that occupies the causal role of pain for the appropriate population.

The Tyrant steered his coagulant gaze to the madman, who was snapping his fingers again.  The madman was in pain because his brain was in that painish-feeling state, however weirdly caused and manifested; and that state was the painish-feeling state because... because... because it was the brain state occupying the causal role of pain, or maybe just selected to function painwise, not for the madman in particular but rather for... whom?  Normal people?  Our evolutionary ancestors?  The madman’s own past self?  His mom?

A thought swelled inside the Tyrant.  “What counts as the appropriate population?”

The Philosopher answered:

Perhaps (1) it should be us; after all it’s our concept and our word.  On the other hand, if it’s X we’re talking about, perhaps (2) it should be a population that X himself belongs to, and (3) it should preferably be one in which X is not exceptional.  Either way, (4) an appropriate population should be a natural kind – a species perhaps.

(An advisor whispered to the Tyrant, “Although Mr. Lewis does not seem very confident, it is the best theory the philosophers have.”)

“I shall try it!” proclaimed the Tyrant.  Lovingly substituting himself in for X, he turned his attention to criterion (1).

From the doctors’ scans, the Tyrant knew that he was in Brain State #1117A.  (The brain picture was entirely clear on the card before him, with a small “#1117A” handwritten in the lower right corner in pretty green letters with hearts.)  Brain State #1117A was the type of state apt, in normal human beings, to be caused by pinchings, pokings, excessive pressure, excessive heat, and other types of tissue stress, and to cause writhing, screaming, moaning (the Tyrant here emitted a noise which might have been a moan), avoidance, answering “Yes!” when asked whether one still has that miserable pain (assuming one knows English and wants to tell the truth), and so forth.  In short, Brain State #1117A filled the causal role of pain.  Brain State #1117A was exactly the Tyrant’s problem.  The doctors could not eliminate the state, but philosophy might alter its significance.

Criterion (1) seemed to require that to be pain, Brain State #1117A must play the causal role of pain for the population whose word and concept “pain” is.  The word “pain” was at that time a piece of standard English.  The Tyrant’s approach, then, would be to kill everyone who had enough English to use the word.  He issued the orders and it was done.  The rolls of the dead included, sadly, David K. Lewis, the madman, the Martian, and all of the tyrant’s advisors and doctors, including the one who had drawn the little hearts.  However, the Tyrant’s headache persisted.

It occurred to the Tyrant that he himself still knew English.  Perhaps for this reason alone “pain” endured?  So the Tyrant taught himself Sanskrit, and with the help of Sanskrit-speaking hypnotists he forgot English.  [Editor’s note: The reader confused to find this text in English should be reminded that this ancient language was later reconstructed from archival records.  ईशावास्यमिदं सर्वं!]  Brain State #1117A and his headache persisted.

The Tyrant gazed wisely upon a coconut, like Aristotle in the famous painting.  It was foolish, he decided, to expect that eliminating a word (what word was that again?) would end his pain.  Surely, if criterion (1) had merit, it would be in virtue of the concept of pain, which is shared across languages.  His course was clear.  He eliminated from the universe the concept of pain.  This he did by setting a timer.  For exactly 10,000 seconds, the intelligence of all entities in the universe would be reduced to that of frogs; then intelligence would be restored.  He arranged for a video camera and brain scanner to record him throughout the crucial interval.  Then he flipped the switch, expecting relief.

Brain State #1117A remained.  The Tyrant squirmed and bellowed, banged his fist against his head, flopped upon the floor and cried.  He laid down no memories of these moments (frogs being notoriously forgetful), but after the 10,000 seconds had elapsed, he reviewed the records.  The evidence did not incline him to believe that his pain had been eliminated.

Perhaps, the Tyrant thought, concepts can be invented but never destroyed?  He invented the concept of utter peaceful bliss, apt to be caused, in Tyrants of a certain natural sort, by pokings, burnings, etc., and apt to cause (despite the bliss), writhing, groaning, and sincere belief in the existence of one’s own pain.  He rested his mind smoothly within this thought.  As far as he could tell, however, this conceptual intervention gave him no help.  (The Tyrant did have to admit he might have only falsely believed it gave him no help.  In light of this possibility, he founded a Bureau dedicated to forming new awesome concepts of Tyrannical delight under all possible conditions.)

The Tyrant grew concerned that he had been focusing on the wrong criterion.  The Philosopher had never said that the relevant comparison population must meet all of the criteria.

The Tyrant contemplated criteria (2)-(4) – that “it should be a population that X himself belongs to”, that “it should preferably be one in which X is not exceptional”, and that either way “an appropriate population should be a natural kind – a species perhaps”.  Though the Tyrant humbly knew that he was in no way exceptional (criterion (3)), that could be changed!  He had learned of a small group of people in whom Brain State #2324B rather than Brain State #1117A played the causal role of pain.  In them, Brain State #1117A played the causal role of mild annoyance at someone else’s bad jokes – a far preferable state!  The Tyrant might kill everyone except for this small group of people.  He would then belong to a species in which Brain State #1117A normally played the causal role of annoyance at bad jokes, not the causal role of pain.  He would be merely a “mad” member of this population.  Brain State #1117A would then become, for him, the feeling of mild annoyance at bad jokes, though with madly atypical causes and effects.  Relief was nigh!

The Tyrant thus attempted a new round of anaesthesia by genocide, directed this time not only at English speakers.  Corpses filled the rivers, piled the beaches, drifted socially across the sea.  However, the Tyrant’s headache endured.  He moaned and writhed, pictured a vise breaking his head like the broken heads of his beloved dead in their sleeps upon the palace stairs.  (A headache is a lonely thing!)

The Tyrant firmed his resolve.  He accelerated time and allowed the survivors to breed for several generations.  To prevent speciation, he produced daughters and sons with them.  He told the worst knock-knock jokes he knew.  He watched their brains light up with #1117A while they groaned.  His envy of their #1117A’s was taller than a mountain.  Why must he alone among humans experience #1117A as pain?

The Tyrant drove himself mad now in a different way – “mad” in the strict Lewisian sense of course, but this time relative to the population of his birth rather than relative to existing human beings.  He had already been half-mad, since the causes of his #1117A had long been atypical; the state endured endlessly regardless of pokings, pinchings, or whatever.  What remained was only to alter the effects.  The Tyrant’s neuroscientists rewired his motor outputs so that Brain State #1117A caused him to snap his fingers instead of writhing.  They rewired his attention centers so that Brain State #1117A led him to think about mathematics.  For a while, they paralyzed him so that no motor outputs were possible at all.  They hypnotized him so he would no longer say to himself, in inner speech, with a feeling of assent, “I am in pain”.  Instead, he would say to himself “I feel entirely pain free.”  They clipped his memory so that he could no longer form new memories of any moments of pain.  They de-efferented his wincers.  Throughout these procedures, Brain State #1117A burned on.

The Tyrant donned the top hat and monocle of madness and considered whether he was still in pain.

How could he know?  He couldn’t trust his clipped memory.  He couldn’t trust his manipulated inner speech and feelings of assent.  He wasn’t sure how to properly interpret his tricked-up behavioral signs.  Nor did it help to say earnestly to himself “I’m experiencing this” in hopes of infallibly referring to his current phenomenal state.  By depriving himself of trustworthy information about his mentality, the Tyrant had made himself only a skeptic!  In a way, his new situation might be worse.  The pain might be continuing, but now with delusion and madness added.  The Tyrant sat upon his throne, snapping his fingers intensely and picturing the Mandelbrot set.  He asked a physician to temporarily reverse one of his hacked-up rewirings: the finger-snapping/writhing motor output crossover.  No sooner did the physician do this than the Tyrant fell to the floor writhing in (apparent) agony – all the while saying to himself, in inner speech, with a feeling of assent, “I am entirely pain free”.  The Tyrant was unsettled and had the finger-snapping hack reinstated.

The Tyrant paced along the beach (cleared of corpses generations ago), contemplating his humanity.  Although it was now normal in the currently existing human population for Brain State #1117A to play the causal role of annoyance at someone else’s bad jokes, that causal role was perhaps not normal among the human species considered across the vasty spans of time.  His subjects, then, might be as mad as he, in anguish at his knock-knock jokes, though they didn’t know it!  To fully ensure that Brain State #1117A would not occupy the causal role of pain in the species to which he belonged, the Tyrant would have to change species.

The Tyrant had radical gene therapy.  He moved to a new land.  He became reproductively isolated from human beings, giving birth now to children with substantially different traits and who could not interbreed with human beings, but who could and did further interbreed with him.  In these beings, as in the Tyrant, Brain State #1117A endured persistently, causing them to snap their fingers.  The mothers of this new species instinctively used their long teeth to perform the snapping/writhing motor crossover when their babies were less than one week old.  (Rare was the baby whose mother never performed this operation; such babies writhed from neglect and eventually perished.  Healthy babies of course snapped instead, after their first week.)  Since the Tyrant was unsure whether an entity could change species during its lifetime, he had himself destroyed and two molecule-for-molecule duplicates of himself simultaneously constructed out of entirely new materials six days later, one of whom promptly murdered the other.

After all this was done, a monocled, long-toothed Tyrant sat crosslegged atop his throne, snapping his fingers, wondering if he was in pain.  He knew what would happen if he had a physician flip his finger-snapping/writhing motor output crossover or if a Sanskrit hypnotist were to re-suggest him backwards, but he no longer knew whether such counterfactuals were relevant to the question.  He wished he could have the philosopher-magician David K. Lewis back from the dead.

If the number of universes is infinite, this story is true.




Hill, Christopher S. (2009).  Consciousness.  Cambridge: Cambridge.

Lewis, David K. (1980).  Mad pain and Martian pain.  In N. Block (ed.), Readings in philosophy of psychology.  Cambridge, MA: Harvard.

Tye, Michael (1997).  A representational theory of pains and their phenomenal character.  In N. Block, O. Flanagan, and G. Güzeldere (eds.), The nature of consciousness.  Cambridge, MA: MIT.

Tye, Michael (2000).  Consciousness, color, and content.  Cambridge, MA: MIT.

Tye, Michael (2005a).  Another look at representationalism about pain.  In M. Aydede (ed.), Pain.  Cambridge, MA: MIT.

Tye, Michael (2005b).  In defense of representationalism: A reply to commentaries.  In M. Aydede (ed.), Pain.  Cambridge, MA: MIT.