geographic objects and their categories barry smith & david m. mark university at buffalo

Geographic Objects and Their Categories

Barry Smith & David M. MarkUniversity at Buffalo

Outline

What is Ontology? Where Do Geographic Categories Come From?The Truth About EarthObjects and Fields: The Individuation ProblemData Standards and Cultural/Linguistic

RelativismSome Empirical ResultsSummary

Ontology

Ontology studies the constituents of realityAn ontology of a given domain describes in

formal terms the constituents of reality within that domain

The ontology also describes the relations between these constituents, and also the relations between constituents of one domain and others

(Smith)

Ontology of Geographic Things

Geographic things are not merely located in space, they typically are tied intrinsically to space in such a way that they inherit from space many of its structural (mereological, topological, geometrical) properties

The role and nature of boundaries is especially important

Geographic Things, continued

Individuation criteria are much more likely to be ambiguous, and to vary across individuals and cultures, and

Classification (categorization) and individuation probably are not independent

Where do Categories Come From?

Nature?Bargains within speech communities?Affordances?

Are Categories in the World?

Natural Kinds “Cut nature at its joints”

This seems clearly to be the case for the biological world, including human artifacts and constructions

But does the inorganic world have these natural ‘joints’ between categories?

Benjamin Lee Whorf

Sapir-Whorf and linguistic relativism “We cut nature up, organize it into concepts,

and ascribe significance as we do, largely because we are parties to an agreement to organize it in this way—an agreement that holds throughout our speech community and is codified in the patterns of our language. (Whorf, 1940, pp. 213-214.)

Affordances

J. J. Gibson has provided a valuable account of the perceived world, which he presented as a prelude to his accounts of human visual perception

A key part of his model is the concept of affordances

Affordances

“The affordances of the environment are what it offers the animal, what it provides or furnishes, either for good or evil.”

James J. Gibson, “The Ecological Approach to Visual Perception.”

Geographic Affordances

Conjecture: Parts of the environment gain meaning, become things, mainly according to the activities that they afford.

Parts of the Earth's surface that afford more or less the same activities may be considered to belong to the same category.

Geographic Affordances

Mountains afford climbingMountains also afford navigation when

they serve as landmarks Lakes afford fishing, the obtaining of

drinking water, swimming, travel by boatForests afford wood gathering, hunting,

hiding from enemiesEtc.

Some Truths: Water and Life

Some 70 percent of the surface of Earth is covered by liquid water, and the planet is surrounded by a gaseous envelope called the atmosphere.

Plants cover most parts of the land surface, and animals (including humans) move about among those plants.

Ontology for Science?

A complete ontology of geographic phenomena will have to incorporate all of these scientific facts and more, but are they relevant to our current effort to describe primary geographic theory, Naive geography, geography relevant to action?

Land Forms

Forces from above and below have shaped the form of the surface of Earth and other rock planets.

The influence of gravity is a dominant factor—loose material tends to move away from high areas toward lower ones in a process generally termed erosion.

Land Forms

Steeper slopes are less stable than gentle ones and so over time there is a tendency toward leveling unless other forces act against that.

Overhanging cliffs are extremely rare, so the elevation of the Earth's surface can be conceptualized as a single-valued function of horizontal position, that is, as a continuous field.

Land Forms

Generally speaking, this is how science has modeled the geometry of the Earth's surface.

Scientists who attempt to account for or model hydrology and sediment transport conceptualize the Earth's surface as composed of slope gradients and orientations over a field of elevations.

Land Forms

This idea of the single-valued field of elevations as a representation of the form of the Earth's surface has been incorporated implicitly or explicitly into representations of earth form developed for computers in the 1950s and since.

Topography Experienced

The topographic environment as experienced by people is very different from this

It is the same environment, of course, but experienced through human senses in the context of human activities and needs.


When viewed from the surface of the Earth by a creature between 1 and 2 meters tall, variations of surface elevation of tens, hundreds, or thousands of meters dominate the experienced landscape, while at the same time, the curvature of the geoid, of the horizontal, is almost imperceptible.


When people see, learn, and describe a landscape, they do not think of it as a field or surface.

Rather, they consider it to be composed of objects or things, presumably based on some combination of gestalt visual perception and the perception of affordances.


Visual perception tends to identify convex surfaces are forming objects, and Gibson wrote of detached objects as having completely closed surfaces making them moveable, or as attached objects that forms parts of the surfaces of larger things.


The perceived surface of the Earth appears to follow this principle and to be dominated by convex rather than concave parts.


In an experiment to be detailed later, in which subjects were asked to list examples of geographic features, objects, or things, mountain was the most frequent example, listed by 151 of 263 subjects.

A secondary form of land convexity, hill, was listed somewhat more often (by 43 subjects) than was the most frequent concave form, valley (39 subjects).


Evidently, mountains are the quintessential geographic things to everyday people, yet they hardly appear in the scientific models. Nor do they appear as objects in our geographic databases.


Mountains and the like also have been neglected in philosophers' ontologies (e.g. Aristotle), which have taken as their paradigm for objects complete moveable things with their own boundaries (such as people, or atoms, or planets), what Gibson called "detatched objects".

Objects and Fields: The Individuation Problem

Do mountains really exist?


Mont Blanc


Yes, obviously! But what does “exist” mean here?Do things (objects? entities?) exist that

are members of the category “mountain”?Perhaps “mountains” are just convex parts

of the elevation fields

Which part is Mount Everest?

Data Exchange Standards

and Linguistic Relativism

Standard Facilitate Data ExchangeCommon Ontology facilitates Semantic

InteroperabilityBut what about cultural or linguistic

differences in categories?An Example: Étangs

Semantics for Geospatial Data Exchange

An Example from the DIGEST standard (Digital Geographic Information Working Group, DGIWG)

BH080: A body of water surrounded by land

US Lake / Pond

FR Lac / Étang

GE See / Teich

IT Lago / Stagno

NL Meer / Plas / Vijver

SP Lago / Laguna

UK Lake / Pond

Semantics for Geospatial Data Exchange

Are “ponds” in English the same as “étangs” en Français?

BH080: A body of water surrounded by land

US Lake / Pond

FR Lac / Étang

GE See / Teich

IT Lago / Stagno

NL Meer / Plas / Vijver

SP Lago / Laguna

UK Lake / Pond

Étang de Berre

Avec ses 75 km de périphérie et une profondeur ne dépassant pas 9 mètres, cet étang gigantesque est relié à la Méditerrannée par un canal à l'ouest, et par un souterrain à l'est, en direction de Marseille

Things are not always what they say they are ...

Étang de Berre

Ceci n’est pas un «pond»!

Étang de Berre

So, is it a lake?

Étang de Berre

No! In English it would be called a “lagoon”!

Another Kind of Water Body: Lagoon

BH190: Open body of water separated fromthe sea by sand bank or coral reef

US Lagoon / Reef Pool

FR Lagon / Lagune

GE Lagune

IT Laguna

NL Lagune / Strandmeer

SP Albufera

UK Lagoon / Reef Pool

Conceptual Model for Water Bodies

“A body of water surrounded by land”“Open body of water separated from the sea by a sand

bank or coral reef”

Kinds of water bodies may be distinguished by Size Origin Water quality ...

}-

Conceptual Model for Water Bodies

Different Languages

Different languages may give different weights to these factors

Consider English and French

Geographic Categories

Some Empirical Results

Category Norms (following Battig and Montague, 1969)

“For each of the following categories, please write down as many items included in that category as you can in 30 seconds, in whatever order they happen to occur to you”

Subjects were then given a series of category labels

Subjects

263 students from the “World Civilization” general education course at UB, Fall 2000

Additional subjects in Finland, Croatia, Poland, Guatemala, and England

What Difference Does the Exact Question Make?a kind of geographic feature a kind of geographic objectsomething that could be portrayed on a

map(concept, entity, phenomenon)

English Norms, ‘feature’ highest

term feature object map-pable

total F

mountain 48 23 25 96river 35 18 31 84lake 33 13 21 67ocean 27 16 18 61hill 20 9 0 29valley 21 7 0 28plain 19 6 1 26plateau 17 4 0 21desert 14 6 0 20volcano 10 4 0 14stream 6 2 1 9

English Norms, ‘object’ highest


total F

map 0 17 0 17

globe 0 11 0 11

peninsula 8 10 1 19

compass 0 8 2 10

land 2 6 0 8

rock 1 6 0 7

atlas 0 6 0 6

English Norms, ‘mappable’ highest


total F

city 1 4 30 35road 1 2 27 30country 2 6 23 31state 0 5 15 20continent 1 10 12 23town 0 5 8 13street 0 1 8 9highway 1 0 7 8park 0 0 6 6county 0 2 5 7building 0 1 5 6

information systems databases organizations language-communities sciences religions maps

= a system of concepts pertaining to a given domain

... concepts that are more or less coherently specified

Each involves a certain conceptualization

– a common system of concepts in terms of which different information communities can talk to each other and exchange data

Why make ontologies?

To provide a stable forum for translation and interoperability as between different conceptualizations

KR Ontology

deals with the generated correlates of both good and bad conceptualizations

– with surrogate created worlds – with ‘universes of discourse’

Not all conceptualizations are equal

Bad conceptualizations: story-telling, myth-making, legacy information systems based on insecure foundations ...

Good conceptualizations: science (mostly) what else?

Two sorts of conceptualizations bad conceptualizations = relate merely to a created, surrogate world

good conceptualizations = transparent to some independent reality beyond

A transparent conceptualization is a partition of reality

Ontology should foster transparent conceptualizations (veridical perspectives on reality)

It should provide a constraint on conceptualizations (Guarino)

Transparent conceptualizations

The sciences provide us with a good first clue as to what these are

Scientific conceptualizations = those based on theories which

have survived rigorous empirical tests

Science and prediction

The perspectival cuts through reality yielded by the different sciences capture dimensions of reality in relation to which we can develop predictive theories

Scientific conceptualizations are transparent

they illuminate some features of the underlying realityand trace over others

Objects vs. fields

form

matter

scientific reality = (roughly) fields(matter + energy)

common-sense reality = objects

plus attributes and processes

quantitative

qualitative

The opposition objects vs. fields in the realm of accidents too

Objects vs. fields in the realm of accidents too

form

matter

R=175, G=54, B=24

‘red’

Two different perspectives on reality:

the qualitative (objects, attributes, processes)

the quantitative (fields: matter, energy)

both transparent to the reality beyond

(one is cruder, coarser than the other)

Two different perspectives:

Aristotle helps us with the qualitative perspective (of objects, attributes, processes)

Science helps us with the quantitative perspective (of fields)

How to produce a theory of the common-sense geographic realm ?

1. theory of vagueness

2. mereology (theory of wholes and parts, including negative parts)

3. the theory of fiat boundaries

4. qualitative geometry and qualitative topology

Theory of vagueness

How can -based conceptualizations be transparent, if the world is shaped like this

?

via some sort of distortion ?

(so that common-sense concepts would be like cookie-cutters, cleaving reality at non-existing joints) ?

No: common sense does not lie

... our common-sense concepts are soft at the edges

and are employed by us

accordingly

they have a built-in sensitivity to thedifference between focal and borderline instances

focus

penumbra

Fuzzy logic

illegitimately transforms this qualitative space into a quantitative field of precise probability assignments

x is red with probability 93.748 %

How to produce a qualitative theory of vagueness ?

– a theory of the way in which our common-sense concepts apply to reality in such a way as to comprehend an opposition between focal and penumbral instances ?

Negative parts (holes): not made of matter

Aristotle neglects features of the common-sense world not made of matter

Examples: property rightsobligations

institutionsspatial regionsspatial boundaries

In the realm of table-top space boundaries are not ontologically problematic:

table-top objects have clear boundariesthey never share boundariesthey never overlap they do not flow, merge, splitthey do not change their genus as they

growthey do not change their genus from

season to season

they do not change their genus according to what they abut

contrast: mountain – valley

Bona Fide Objects

The objects of table-top space have bona fide boundaries

= boundaries which exist independently of our cognition

Fiat Boundaries

= boundaries which exist only in virtue of our demarcations

Fiat objects = objects with fiat boundaries

Examples of fiat objects Two-dimensional fiat objects: census tracts postal districts Wyoming

Three-dimensional fiat objects

the Northern hemisphere the 3-dimensional parcels to

which mineral rights are assigned the Klingon Empire

Controlled Airspace

Holes in the ground

Bone fide boundaries at the floor and walls

with a fiat lid

What is a valley ?

Grand Canyon

mountain is the most prominent kind of geographic object in the common-sense ontology. But it is absent from the scientific ontology as a kind of thing

... the latter includes slope steepness and direction at every point, but represented as fields

What is a mountain ?

Mountain bona fide upper boundaries with fiat base:

Basic Formal OntologyConcrete Entity

[Exists in Space and Time]Concrete Entity

[Exists in Space and Time]

Entity in 3-D Ontology[Endure. No Temporal Parts]


Entity in 4-D Ontology[Perdure. Unfold in Time]Entity in 4-D Ontology

[Perdure. Unfold in Time]

Processual EntityProcessual EntitySpatio-Temporal Region

Dim = T, T+0, T+1, T+2, T+3Spatio-Temporal Region

Dim = T, T+0, T+1, T+2, T+3

Spatial Regionof Dimension 0,1,2,3

Spatial Regionof Dimension 0,1,2,3 Dependent EntityDependent Entity

Independent EntityIndependent Entity

Quality (Your Redness, My Tallness)[Form Quality Regions/Scales]

Quality (Your Redness, My Tallness)[Form Quality Regions/Scales]

Role, Function, PowerHave realizations (called: Processes)

Role, Function, PowerHave realizations (called: Processes)

Substance[maximally connected causal unity]


Boundary of Substance *Fiat or Bona Fide or MixedBoundary of Substance *

Fiat or Bona Fide or Mixed

Aggregate of Substances * (includes masses of stuff? liquids?)


Fiat Part of Substance * Nose, Ear, Mountain


Process [Has Unity]Clinical trial; exercise of role

Process [Has Unity]Clinical trial; exercise of role

Fiat Part of Process*Fiat Part of Process*

Aggregate of Processes*Aggregate of Processes*

Instantaneous Temporal Boundary of Process (= Ingarden’s 'Event’)*

Instantaneous Temporal Boundary of Process (= Ingarden’s 'Event’)*

Quasi-ProcessJohn’s Youth. John’s Life

Quasi-ProcessJohn’s Youth. John’s Life

Quasi-Quality Prices, Values, Obligations

Quasi-Quality Prices, Values, Obligations

Quasi-SubstanceChurch, College, Corporation

Quasi-SubstanceChurch, College, Corporation

Quasi-Role/Function/PowerThe Functions of the PresidentQuasi-Role/Function/Power

The Functions of the President

Basic Formal OntologyConcrete Entity

[Exists in Space and Time]Concrete Entity

[Exists in Space and Time]



Independent EntityIndependent Entity







where does the mountain start ?

Everest

Mount Everest

Mont Blanc from Chatel

Question:

Are mountains bona fide or fiat objects?

Did mountains exist before human cognitive agents came along?

Bona fide mountain (tops)

Miquelon_and_Saint_Pierre_Island

Are all holes fiat objects ?

hollows

tunnels

cavities

Did hollows and tunnels exist before human cognitive agents came along?

Rabbit holes, worm holes

Geospatial forms as precursors of evolution

What is a lake ?

A filled hole ?

What is a lake ?

1. a three-dimensional body of water ?

2. a two-dimensional sheet of water ?

3. a depression (hole) in the Earth’s surface (possibly) filled with water ?

are dry lakes lakes?or merely places where lakes used to be?

Each of these has problems: If we take:

1. a lake is three-dimensional body of water

then a lake can never be half full

Open problem: ontology of liquids

What’s the point ?

Common-Sense Reality

Why is it important that we get the ontology of common-sense reality right?

Science is important for engineering Well, ... it’s important that we get the

ontology of physics right because physics is a basis for engineering:

... bridges and airplanes are

engineering products in which physical reality is embedded

Many biological sciences relate to the common-sense world of qualitative forms:

Ecology (need for ontology of niches or habitats)

Biogeography

Palaeontology = science of common-sense reality as it existed before human beings evolved

Why is naive ontology important?

It’s important that we get the ontology of common-sense reality right ...

... because it is common-sense ontology which underlies medicine

where does the mountain start ?

geographic objects and their categories barry smith & david m. mark university at buffalo

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