The five senses and perception — The World, with the Evidence

Black-and-white anatomical drawing of a human eye. — The human eye (drawing by Henry Vandyke Carter, before 1858). Henry Vandyke Carter, Public domain, source

How many senses does a human being have?

Five, is the usual answer. But what should we call the thing that lets you know, with your eyes closed, where your hand is?

What the count of five leaves out

Sight, hearing, smell, taste, touch.

Balance? It has its own organs, in the inner ear. When it goes wrong, your head spins.

The position of the body? You know where your feet are without looking at them. That information does come from somewhere.

Temperature? Pain? Hunger, thirst, the urge to breathe?

Each of these has receptors, nerves, processing. So why five?

Because someone chose five, a very long time ago, keeping the senses that face outwards and are consciously perceived. It is a way of dividing things up, not a tally.

Specialists today propose several, depending on the criteria chosen — and there is no single answer.

The principle comes up often on this site: to count, you must first decide what you are counting.

The tongue map

This case lets us follow the error step by step.

This diagram may be familiar: the tongue divided into zones, sweet at the tip, bitter at the back, sour along the sides.

It is wrong. It does not come from a failed experiment: it comes from a misread graph.

A German study from the early twentieth century showed differences in sensitivity across regions of the tongue — differences of degree, not exclusive zones. Reproduced in 1942 in an American book, the graph was interpreted as a map of territories.¹

It was refuted in 1974, and one detail makes the refutation delicious.

The study measured detection thresholds at several points on the tongue and palate. It found differences — even more marked than had been reported before.²

But they did not point the way the map did. Contrary to older data, bitter was detected better at the front of the tongue than at the back.³

The exact opposite of what the diagram teaches.

Yet the myth remains persistent.⁴

The second layer

The most instructive part of this story is what almost nobody mentions.

That 1974 study is now cited everywhere as proof that there is no difference between regions of the tongue.⁵

That is not what it says. It shows that the differences exist — they are simply not those of the map, and they are not exclusive territories. Recent work notes that this nuance in its data has been overlooked, precisely because the article is cited only to demolish the myth.⁶

The point deserves a pause. The false diagram was simplified as it circulated. Then the refutation of the diagram was simplified in its turn, in the other direction.

The same mechanism, applied twice, on both sides. An idea travels badly, whether it is true or false.

How many senses, exactly?

Five, we are told. The list comes from Aristotle, nearly two thousand four hundred years ago.⁷

It leaves out several senses, among them:

Proprioception — knowing where your limbs are without looking at them. Touching your nose with your eyes closed is enough to put it to work.
Equilibrioception — balance, picked up in the inner ear.
Thermoception — heat and cold.
Nociception — the detection of damage, distinct from touch.
Interoception — the family of senses that reports on the inside of the body: hunger, thirst, the need to breathe, the beating of the heart.
Chronoception — the perception of time passing, which some add to the list despite its having no dedicated organ.⁸

So, how many?

Specialists propose very different numbers: at least ten, more probably twenty-one, and up to thirty-three for the finest-grained counts.⁹

Three, five, ten, twenty-one, thirty-three.

None is wrong. The answer depends partly on what we are willing to count as a “sense”.¹⁰

And the range is wide. Depending on the criterion chosen, we arrive at three broad families (chemical, mechanical, light), or at ten commonly accepted senses, or at twenty-one, or — for the finest-grained counts — up to thirty-three.¹¹

You can count “touch” as one sense, or count pressure, vibration, stretch, temperature and pain separately. The body does not change. The classification does.

Interactive

How many senses?

Five senses, people have said since Aristotle: sight, hearing, smell, taste and touch. But how are they counted?

The question

Do we really have five senses?

Without JavaScript, here are the animation’s data.

Five ways of counting
Number	Division	Source
3	three broad families: chemical, mechanical, light	1
5	Aristotle’s list	2
10	at least ten commonly accepted senses	3
21	more probably twenty-one	3
33	up to thirty-three, for the finest-grained counts	3

The three broad families
Family	Source
chemical	1
mechanical	1
light	1

Aristotle’s five senses
Sense	Source
sight	2
hearing	2
smell	2
taste	2
touch	2

Two senses Aristotle leaves out
Sense	What it picks up	Source
proprioception	knowing where your limbs are without looking at them	4
interoception	the inside of the body: hunger, thirst, the need to breathe	5

Beyond five, the boxes carry no names: they only show how many senses are counted under each division.

The takeaway Three, five, ten, twenty-one, thirty-three: none of these numbers is wrong. It depends on how we divide up our sensory systems.

Photo credits 5

The eye in section: engraving from Henry Fox Hewes, Anatomy, Physiology and Hygiene for High Schools, 1900. Henry Fox Hewes, Public domain, source
The auricle of the ear, outer surface: plate 904 of Gray’s Anatomy, drawn by Henry Vandyke Carter. Henry Vandyke Carter, Public domain, source
The nasal cavity in section, with the nerves of smell: engraving from Jerome Walker, Anatomy, Physiology and Hygiene, 1900. Jerome Walker, Public domain, source
The upper surface of the tongue and its papillae: engraving by Henry Vandyke Carter for Gray’s Anatomy, 1860. Henry Vandyke Carter, Public domain, source
The palm of the hand: engraving from Gray’s Anatomy, 1897 edition. Henry Gray and Henry Vandyke Carter, Public domain, source

Sources 5

Arney, Kat, “Myth: You have five senses”, The Naked Scientists, 14 March 2017, programme text, passage on the “reductionist” approach.
And if you want to get really reductionist about it all, you could argue that humans have just three senses, based on the kind of input coming into the nervous system - mechanical senses that measure physical changes (which would include touch, hearing and proprioception), light detection, and chemical sensing, which takes in taste, smell and all the sensory inputs that come from chemical signals within the body.
Open access open the source · checked on 27 October 2026
Aristote, De l’âme, livre II, chap. 6-11, et livre III, chap. 1, book III, chapter 1 (424 b 22), first sentence; English translation by J. A. Smith (the MIT page does not show Bekker numbers).
That there is no sixth sense in addition to the five enumerated-sight,hearing, smell, taste, touch-may be established by the following considerations:
Public domain open the source · checked on 27 October 2026
Howes, David, Sensorium: Contextualizing the Senses and Cognition in History and Across Cultures, Cambridge University Press, “Elements in Histories of Emotions and the Senses” series, 2024, excerpt published by the publisher (pp. 1-8), section 1, p. 3.
Sensory scientists will object that the list does not stop at six, that thanks to advances in neurobiology we now know that there are at least ten senses, but more likely twenty-one, and radical estimates put the number as high as thirty-three (Durie 2005).
Open access open the source · checked on 27 October 2026
Betts, J. Gordon et al., Anatomy and Physiology, OpenStax, Rice University, section 14.1, subsections “Structural Receptor Types” and “Sensory Modalities”.
Finally, a proprioceptor is a receptor located near a moving part of the body, such as a muscle, that interprets the positions of the tissues as they move. […] General senses often contribute to the sense of touch, as described above, or to proprioception (body position) and kinesthesia (body movement), or to a visceral sense (sense associated with the internal organs), which is most important to autonomic functions.
Open access open the source · checked on 27 October 2026
National Institutes of Health (NCCIH and participating institutes), “Notice of Special Interest (NOSI): Promoting Research on Interoception and Its Impact on Health and Disease”, NOT-AT-21-002, 22 January 2021, section “Terminology for Interoception Research”.
Interoception includes the processes by which an organism senses, interprets, integrates, and regulates internal signals.
Open access open the source · checked on 27 October 2026

Open full page · All interactives

Why five survived

Not because it is the right number, but because it is simple, old and easy to remember.

It is a very pure case of a common phenomenon: a practical classification that ends up being taken for a description of reality.

The senses in the five-way division have something in common: they are the five senses that point outwards, and whose organ can be pointed to on a face. The missing ones are mostly those that look inwards — and that have no visible organ to point to.

We counted what could be seen.

An honest caveat

A molecule abundant in the human eye, cryptochrome, can respond to magnetic fields: a study showed this in the laboratory, in flies. A more recent study, carried out on a very large number of flies, nevertheless found no sign of a magnetic sense in them.¹²

But no conscious magnetic sense has been demonstrated in humans. Responding is not perceiving, and this page will not take that step. For ultraviolet and the radiation our eyes do not pick up, see Entry 4.14 The electromagnetic spectrum. For magnetoreception in animals, see Entry 5.14 Social behaviour and migration, where it is covered along with its mechanisms.¹³

Perceiving is interpreting

The most important point of this page remains.

We do not receive the world. We reconstruct it — constantly, from incomplete signals, filling in the gaps with what we expect to find.

This site gives two examples of this, in two very distant fields:

The canals of Mars. For decades, competent astronomers drew straight lines on the surface of Mars (see Entry 1.14). There are none. The instrument produced smudges at the limit of visibility, and the eye — which looks for shapes — joined them up. Then, once the word “canals” had been coined, others saw them in turn.
Colours. An apple is not red. It reflects a certain light, which the eye picks up and the brain interprets as red.¹⁴

In both cases: what is perceived is already an interpretation.

This does not mean that nothing is real. It means that between the world and the one who perceives it there is processing — and that this processing has rules, which can be studied and sometimes caught out.

And what we will not write

One last thing, and it concerns a rule of this site.

We never write “you see”, “you hear”, “you feel” as if it went without saying for everyone.

Some readers of this page are deaf. Others are blind. Others perceive differently, more intensely or less.

This is not a more polite way of writing. It is a more accurate one. A sentence that assumes a typical reader describes reality poorly — and it describes it poorly for everyone, not only for those it excludes.

Note 1

Süß wird an allen Punkten der Zungengeschmackszone empfunden, aber in abgestufter Intensität. […] Bitter wird an allen Punkten der Zungengeschmackszone empfunden, aber in verschiedenen Intensitätsgraden. […] Salz wird an allen Punkten der Zungengeschmackszone empfunden und zwar in annähernd gleicher Intensität.

Hänig, David P., “Zur Psychophysik des Geschmackssinnes”, Philosophische Studien, vol. 17, 1901, p. 576-623

The origin is most likely a book written by Harvard University’s Edwin Boring in 1942. […] Thus, Hänig’s result that sweet thresholds were slightly lower on the front of the tongue and bitter thresholds were slightly lower on the back was misconstrued and turned into the notion that we taste sweet on the front of our tongues, bitter on the back, etc.

Wolfe, Jeremy M. et al., Sensation and Perception, 4th ed., Sinauer Associates, 2015, companion website, essay 15.1 “Scientific Urban Legend—The Bogus Tongue Map”

See the full note ↓

Note 2

The results showed greater differences between loci than previously reported.

Collings, Virginia B., “Human Taste Response as a Function of Locus of Stimulation on the Tongue and Soft Palate”, Perception & Psychophysics, vol. 16, no. 1, 1974, p. 169-174

See the full note ↓

Note 3

Contrary to older data, the threshold for bitter was found to be lower for the fungiform papillae at the front of the tongue and for the soft palate than for the vallate papillae.

Collings, Virginia B., “Human Taste Response as a Function of Locus of Stimulation on the Tongue and Soft Palate”, Perception & Psychophysics, vol. 16, no. 1, 1974, p. 169-174

See the full note ↓

Note 4

the persistent myth of the tongue map

Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732

See the full note ↓

Note 5

this nuance in Collings' data has presumably been overlooked, as her work is most often cited as a means to debunk the persistent myth of the tongue map

Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732

See the full note ↓

Note 6

other psychophysical data suggest there may be some subtle regional variation in suprathreshold intensity, especially for bitterness

Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732

See the full note ↓

Note 7

That there is no sixth sense in addition to the five enumerated-sight,hearing, smell, taste, touch-may be established by the following considerations:

Aristote, De l’âme, livre II, chap. 6-11, et livre III, chap. 1

See the full note ↓

Note 8

Finally, a proprioceptor is a receptor located near a moving part of the body, such as a muscle, that interprets the positions of the tissues as they move. […] General senses often contribute to the sense of touch, as described above, or to proprioception (body position) and kinesthesia (body movement), or to a visceral sense (sense associated with the internal organs), which is most important to autonomic functions.

Betts, J. Gordon et al., Anatomy and Physiology, OpenStax, Rice University

Interoception includes the processes by which an organism senses, interprets, integrates, and regulates internal signals.

National Institutes of Health (NCCIH and participating institutes), “Notice of Special Interest (NOSI): Promoting Research on Interoception and Its Impact on Health and Disease”, NOT-AT-21-002, 22 January 2021

See the full note ↓

Note 9

Sensory scientists will object that the list does not stop at six, that thanks to advances in neurobiology we now know that there are at least ten senses, but more likely twenty-one, and radical estimates put the number as high as thirty-three (Durie 2005).

Howes, David, Sensorium: Contextualizing the Senses and Cognition in History and Across Cultures, Cambridge University Press, “Elements in Histories of Emotions and the Senses” series, 2024, excerpt published by the publisher (pp. 1-8)

See the full note ↓

Note 10

Perhaps surprisingly, the issue remains controversial, partly because it is not clear exactly what should count as a ‘sense’.

Wilson, Keith A., “How Many Senses? Multisensory Perception Beyond the Five Senses”, Sabah Ülkesi, no. 66, 2021, p. 76-79, abstract

See the full note ↓

Note 11

Sensory scientists will object that the list does not stop at six, that thanks to advances in neurobiology we now know that there are at least ten senses, but more likely twenty-one, and radical estimates put the number as high as thirty-three (Durie 2005).

And if you want to get really reductionist about it all, you could argue that humans have just three senses, based on the kind of input coming into the nervous system - mechanical senses that measure physical changes (which would include touch, hearing and proprioception), light detection, and chemical sensing, which takes in taste, smell and all the sensory inputs that come from chemical signals within the body.

Arney, Kat, “Myth: You have five senses”, The Naked Scientists, 14 March 2017

See the full note ↓

Note 12

human CRY2, which is heavily expressed in the retina, […] can function as a magnetosensor in the magnetoreception system of Drosophila

Foley, Lauren E., Gegear, Robert J. and Reppert, Steven M., “Human Cryptochrome Exhibits Light-Dependent Magnetosensitivity”, Nature Communications, vol. 2, article 356, 2011

testing magnetic field effects on 97,658 flies moving in a two-arm maze […] Our findings therefore cast considerable doubt on the existence of magnetic sensing in Drosophila

Bassetto, Marco, Reichl, Thomas, Kobylkov, Dmitry, Kattnig, Daniel R., Winklhofer, Michael, Hore, P. J. and Mouritsen, Henrik, “No Evidence for Magnetic Field Effects on the Behaviour of Drosophila*”, *Nature, vol. 620, 2023, p. 595-599

See the full note ↓

Note 13

Although many migrating and homing animals are sensitive to Earth’s magnetic field, most humans are not consciously aware of the geomagnetic stimuli that we encounter in everyday life. […] After experimental sessions, participants reported that they could not discern when or if any magnetic field changes had occurred.

Wang, Connie X. et al., “Transduction of the Geomagnetic Field as Evidenced from Alpha-Band Activity in the Human Brain”, eNeuro, vol. 6, no. 2, 2019

See the full note ↓

Note 14

entrée 1.14

Entry 1.14

The facts concerning the canals of Mars are established in Entry 1.14, with their sources

See the full note ↓

Notes and sources

↑
Passage A German study from the early twentieth century showed differences in sensitivity across regions of the tongue — differences of degree, not exclusive zones.
Süß wird an allen Punkten der Zungengeschmackszone empfunden, aber in abgestufter Intensität. […] Bitter wird an allen Punkten der Zungengeschmackszone empfunden, aber in verschiedenen Intensitätsgraden. […] Salz wird an allen Punkten der Zungengeschmackszone empfunden und zwar in annähernd gleicher Intensität.
Source Hänig, David P., “Zur Psychophysik des Geschmackssinnes”, Philosophische Studien, vol. 17, 1901, p. 576-623, pp. 600, 605 and 608: point 1 of the numbered conclusions of the sections on sweet, bitter and salt.
Public domain open the source · checked on 27 October 2026
Passage Reproduced in 1942 in an American book, the graph was interpreted as a map of territories.
The origin is most likely a book written by Harvard University’s Edwin Boring in 1942. […] Thus, Hänig’s result that sweet thresholds were slightly lower on the front of the tongue and bitter thresholds were slightly lower on the back was misconstrued and turned into the notion that we taste sweet on the front of our tongues, bitter on the back, etc.
Source Wolfe, Jeremy M. et al., Sensation and Perception, 4th ed., Sinauer Associates, 2015, companion website, essay 15.1 “Scientific Urban Legend—The Bogus Tongue Map”, essay 15.1 (“Scientific Urban Legend—The Bogus Tongue Map”), 1st paragraph.
Open access open the source · checked on 27 October 2026
↑
Passage The study measured detection thresholds at several points on the tongue and palate. It found differences — even more marked than had been reported before.
The results showed greater differences between loci than previously reported.
Source Collings, Virginia B., “Human Taste Response as a Function of Locus of Stimulation on the Tongue and Soft Palate”, Perception & Psychophysics, vol. 16, no. 1, 1974, p. 169-174, abstract.
Paywalled open the source · checked on 9 September 2026
↑
Passage Contrary to older data, bitter was detected better at the front of the tongue than at the back.
Contrary to older data, the threshold for bitter was found to be lower for the fungiform papillae at the front of the tongue and for the soft palate than for the vallate papillae.
Source Collings, Virginia B., “Human Taste Response as a Function of Locus of Stimulation on the Tongue and Soft Palate”, Perception & Psychophysics, vol. 16, no. 1, 1974, p. 169-174, abstract.
Paywalled open the source · checked on 9 September 2026
↑
Passage Yet the myth remains persistent.
the persistent myth of the tongue map
Source Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732, discussion section of the article.
Open access open the source · checked on 24 October 2026
↑
Passage That 1974 study is now cited everywhere as proof that there is no difference between regions of the tongue.
this nuance in Collings' data has presumably been overlooked, as her work is most often cited as a means to debunk the persistent myth of the tongue map
Source Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732, discussion section of the article.
Open access open the source · checked on 9 September 2026
↑
Passage It shows that the differences exist — they are simply not those of the map
other psychophysical data suggest there may be some subtle regional variation in suprathreshold intensity, especially for bitterness
Source Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732, discussion section of the article.
Open access open the source · checked on 9 September 2026
↑
Passage The list comes from Aristotle
That there is no sixth sense in addition to the five enumerated-sight,hearing, smell, taste, touch-may be established by the following considerations:
Source Aristote, De l’âme, livre II, chap. 6-11, et livre III, chap. 1, book III, chapter 1 (424 b 22), first sentence; English translation by J. A. Smith (the MIT page does not show Bekker numbers).
Public domain open the source · checked on 27 October 2026
↑
Passage Proprioception — knowing where your limbs are without looking at them.
Finally, a proprioceptor is a receptor located near a moving part of the body, such as a muscle, that interprets the positions of the tissues as they move. […] General senses often contribute to the sense of touch, as described above, or to proprioception (body position) and kinesthesia (body movement), or to a visceral sense (sense associated with the internal organs), which is most important to autonomic functions.
Source Betts, J. Gordon et al., Anatomy and Physiology, OpenStax, Rice University, section 14.1, subsections “Structural Receptor Types” and “Sensory Modalities”.
Open access open the source · checked on 27 October 2026
Passage Interoception — the family of senses that reports on the inside of the body
Interoception includes the processes by which an organism senses, interprets, integrates, and regulates internal signals.
Source National Institutes of Health (NCCIH and participating institutes), “Notice of Special Interest (NOSI): Promoting Research on Interoception and Its Impact on Health and Disease”, NOT-AT-21-002, 22 January 2021, section “Terminology for Interoception Research”.
Open access open the source · checked on 27 October 2026
↑
Passage Specialists propose very different numbers: at least ten, more probably twenty-one, and up to thirty-three for the finest-grained counts.
Sensory scientists will object that the list does not stop at six, that thanks to advances in neurobiology we now know that there are at least ten senses, but more likely twenty-one, and radical estimates put the number as high as thirty-three (Durie 2005).
Source Howes, David, Sensorium: Contextualizing the Senses and Cognition in History and Across Cultures, Cambridge University Press, “Elements in Histories of Emotions and the Senses” series, 2024, excerpt published by the publisher (pp. 1-8), section 1, p. 3.
Open access open the source · checked on 27 October 2026
↑
Passage The answer depends partly on what we are willing to count as a “sense”.
Perhaps surprisingly, the issue remains controversial, partly because it is not clear exactly what should count as a ‘sense’.
Source Wilson, Keith A., “How Many Senses? Multisensory Perception Beyond the Five Senses”, Sabah Ülkesi, no. 66, 2021, p. 76-79, abstract, abstract, 4th sentence.
Open access open the source · checked on 27 October 2026
↑
Passage or at ten commonly accepted senses, or at twenty-one, or — for the finest-grained counts — up to thirty-three
Sensory scientists will object that the list does not stop at six, that thanks to advances in neurobiology we now know that there are at least ten senses, but more likely twenty-one, and radical estimates put the number as high as thirty-three (Durie 2005).
Source Howes, David, Sensorium: Contextualizing the Senses and Cognition in History and Across Cultures, Cambridge University Press, “Elements in Histories of Emotions and the Senses” series, 2024, excerpt published by the publisher (pp. 1-8), section 1, p. 3.
Open access open the source · checked on 27 October 2026
Passage we arrive at three broad families (chemical, mechanical, light)
And if you want to get really reductionist about it all, you could argue that humans have just three senses, based on the kind of input coming into the nervous system - mechanical senses that measure physical changes (which would include touch, hearing and proprioception), light detection, and chemical sensing, which takes in taste, smell and all the sensory inputs that come from chemical signals within the body.
Source Arney, Kat, “Myth: You have five senses”, The Naked Scientists, 14 March 2017, programme text, passage on the “reductionist” approach.
Open access open the source · checked on 27 October 2026
↑
Passage A molecule abundant in the human eye, cryptochrome, can respond to magnetic fields: a study showed this in the laboratory, in flies.
human CRY2, which is heavily expressed in the retina, […] can function as a magnetosensor in the magnetoreception system of Drosophila
Source Foley, Lauren E., Gegear, Robert J. and Reppert, Steven M., “Human Cryptochrome Exhibits Light-Dependent Magnetosensitivity”, Nature Communications, vol. 2, article 356, 2011, abstract.
Open access open the source · checked on 24 October 2026
Passage A more recent study, carried out on a very large number of flies, nevertheless found no sign of a magnetic sense in them.
testing magnetic field effects on 97,658 flies moving in a two-arm maze […] Our findings therefore cast considerable doubt on the existence of magnetic sensing in Drosophila
Source Bassetto, Marco, Reichl, Thomas, Kobylkov, Dmitry, Kattnig, Daniel R., Winklhofer, Michael, Hore, P. J. and Mouritsen, Henrik, “No Evidence for Magnetic Field Effects on the Behaviour of Drosophila*”, *Nature, vol. 620, 2023, p. 595-599, abstract.
Open access open the source · checked on 26 October 2026
↑
Passage no conscious magnetic sense has been demonstrated in humans
Although many migrating and homing animals are sensitive to Earth’s magnetic field, most humans are not consciously aware of the geomagnetic stimuli that we encounter in everyday life. […] After experimental sessions, participants reported that they could not discern when or if any magnetic field changes had occurred.
Source Wang, Connie X. et al., “Transduction of the Geomagnetic Field as Evidenced from Alpha-Band Activity in the Human Brain”, eNeuro, vol. 6, no. 2, 2019, “Significance Statement”; § “Results” (neural response to geomagnetic stimuli).
Open access open the source · checked on 27 October 2026
↑
Passage For decades, competent astronomers drew straight lines on the surface of Mars (see Entry 1.14).
entrée 1.14
Editors’ translation Entry 1.14
Source The facts concerning the canals of Mars are established in Entry 1.14, with their sources, facts established elsewhere, with their sources.
Established in other articles, with their sources · checked on 24 October 2026

Bibliography

Aristote, De l’âme, livre II, chap. 6-11, et livre III, chap. 1, public domain (the list of the five senses).
Arney, Kat, “Myth: You have five senses”, The Naked Scientists, 14 March 2017, open access. https://www.thenakedscientists.com/node/190360
Bassetto, Marco, Reichl, Thomas, Kobylkov, Dmitry, Kattnig, Daniel R., Winklhofer, Michael, Hore, P. J. and Mouritsen, Henrik, “No Evidence for Magnetic Field Effects on the Behaviour of Drosophila*”, *Nature, vol. 620, 2023, p. 595-599, open access (nearly a hundred thousand flies tested in a maze: no sign of a magnetic sense). https://doi.org/10.1038/s41586-023-06397-7
Betts, J. Gordon et al., Anatomy and Physiology, OpenStax, Rice University, open access (proprioception, the sense of body position). https://openstax.org/details/books/anatomy-and-physiology
Boring, Edwin G., Sensation and Perception in the History of Experimental Psychology, Appleton-Century, 1942, in libraries (the derived graph, later interpreted as a map of territories).
Collings, Virginia B., “Human Taste Response as a Function of Locus of Stimulation on the Tongue and Soft Palate”, Perception & Psychophysics, vol. 16, no. 1, 1974, p. 169-174, paywalled (differences between zones more marked than previously reported; a lower threshold for bitter at the front of the tongue than at the back, contrary to older data). https://doi.org/10.3758/BF03203270
Craig, A. D. (Bud), “Interoception: The Sense of the Physiological Condition of the Body”, Current Opinion in Neurobiology, vol. 13, 2003, p. 500-505, paywalled (interoception as a distinct family of senses).
Durie, Bruce, “Senses Special: Doors of Perception”, New Scientist, no. 2484, 29 January 2005, p. 33-36, paywalled (the answer that depends on how the sensory systems are divided up; the competing counts: three stimulus families, ten accepted senses, twenty-one, and up to thirty-three).
Foley, Lauren E., Gegear, Robert J. and Reppert, Steven M., “Human Cryptochrome Exhibits Light-Dependent Magnetosensitivity”, Nature Communications, vol. 2, article 356, 2011, open access (human cryptochrome, abundant in the retina, works as a magnetic sensor once produced by fruit flies). https://doi.org/10.1038/ncomms1364
Hänig, David P., “Zur Psychophysik des Geschmackssinnes”, Philosophische Studien, vol. 17, 1901, p. 576-623, public domain (the original study, on differences in thresholds rather than exclusive zones).
Higgins, Molly J. and Hayes, John E., “Regional Variation of Bitter Taste and Aftertaste in Humans”, Chemical Senses, vol. 44, no. 9, 2019, p. 721-732, open access (the nuance in the 1974 data, overlooked because the article is cited only to refute the map; the persistence of the myth; subtle regional variations in intensity). https://doi.org/10.1093/chemse/bjz064
Howes, David, Sensorium: Contextualizing the Senses and Cognition in History and Across Cultures, Cambridge University Press, “Elements in Histories of Emotions and the Senses” series, 2024, excerpt published by the publisher (pp. 1-8), open access. https://assets.cambridge.org/97810095/17225/excerpt/9781009517225_excerpt.pdf
National Institutes of Health (NCCIH and participating institutes), “Notice of Special Interest (NOSI): Promoting Research on Interoception and Its Impact on Health and Disease”, NOT-AT-21-002, 22 January 2021, open access (the definition of interoception, the sensing of the body’s internal signals). https://grants.nih.gov/grants/guide/notice-files/NOT-AT-21-002.html
The facts concerning the canals of Mars are established in Entry 1.14, with their sources.
Sherrington, Charles S., The Integrative Action of the Nervous System, Yale University Press, 1906, public domain (the introduction of the term “proprioception”).
Wang, Connie X. et al., “Transduction of the Geomagnetic Field as Evidenced from Alpha-Band Activity in the Human Brain”, eNeuro, vol. 6, no. 2, 2019, open access (a measured brain response, with no conscious perception demonstrated).
Wilson, Keith A., “How Many Senses? Multisensory Perception Beyond the Five Senses”, Sabah Ülkesi, no. 66, 2021, p. 76-79, University College Dublin repository (CC BY-NC-ND), open access. https://hdl.handle.net/10197/26477
Wolfe, Jeremy M. et al., Sensation and Perception, 4th ed., Sinauer Associates, 2015, companion website, essay 15.1 “Scientific Urban Legend—The Bogus Tongue Map”, open access. https://learninglink.oup.com/public/files/cdn/wolfe4e/essay15.01.html

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