Specification and user’s guide corresponding author: Barry Smith

1Status of this document 1

2Introduction 1

2.1How to read this document 3

2.2Summary of most important changes in BFO 2.0 as compared to BFO 1.1 4

2.2.1Clarification of BFO:object 4

2.2.2Introduction of reciprocal dependence 4

2.2.3New simplified treatment of boundaries and regions 5

Revision of treatment of spatial location 5

Treatment of process predications under the heading ‘process profiles’ 5

Inclusion of relations as part of BFO vs. RO, with changes to relations 5

New relation exists_at added. 5

Relation of containment deprecated 5

Relations of parthood disambiguated 6

Revision of Process 6

2.2.4Future directions 6

3Organization of BFO 6

3.1Entities 6

3.2Relations 7

3.3Primitive and defined terms 8

3.4Definitions 8

3.5Avoiding is_a overloading 9

3.6Universals and classes 10

3.7The monohierarchy principle 11

3.8Determinables and determinates 13

3.9Specializations 13

3.10Role universals 14

3.11Universals defined historically 15

3.12Relations defined for any entity 15

3.12.1The instance_of relation 15

3.12.2The is_a relation 16

3.12.3The exists_at relation 16

3.13The dichotomy of ‘continuant’ and ‘occurrent’ 17

4Specification 18

4.1Relations of parthood 18

4.1.1The continuant_part_of relation 19

4.1.2The occurrent_part_of relation 20

4.1.3Further relations defined in terms of parthood 20

4.2Continuant 22

4.2.1Excursus on frames 23

4.3Relation of specific dependence 24

4.3.1Types of s-dependence 27

4.4Independent continuant 29

4.5Material entity 30

Subtypes of material entity 32

4.5.1Object 32

Causal unity 33

Elucidation of bfo:object 36

Objects can be joined to other objects 37

Objects may contain other objects as parts 38

Conjoined twins 39

4.5.2Object aggregate 39

4.5.3Fiat object part 41

Treatment of material entity in BFO 43

4.6Immaterial entity 44

4.6.1Continuant fiat boundary 45

zero-dimensional continuant fiat boundary 46

one-dimensional continuant fiat boundary 46

two-dimensional continuant fiat boundary 47

4.6.2Site 47

4.6.3Spatial region 49

zero-dimensional spatial region 50

one-dimensional spatial region 50

two-dimensional spatial region 51

three-dimensional spatial region (a spatial volume) 51

4.6.4Location 51

The occupies_spatial_region relation 51

The located_in relation 52

Problem cases for the located_in relation 53

Chaining rules 53

4.7Specifically dependent continuant 54

4.7.1The inheres_in and bearer_of relations 55

4.7.2No s-dependence of higher order 56

4.7.3Quality 58

Relational quality 59

4.7.4Realizable entity 60

Relation of realization 60

4.7.5Role (externally-grounded realizable entity) 61

Optionality of roles 62

Having a role vs. playing a role 62

4.7.6 Disposition (internally-grounded realizable entity) 62

1.1.1Function 64

Defined relations 65

4.7.7Material basis 65

4.8Generically dependent continuant 67

4.8.1Relation of concretization 68

4.8.2Works of music and experimental protocols 69

4.9Occurrent 70

4.9.1Relation of temporal parthood 71

4.9.2Projection relations 73

4.9.3The occupies relations, and occurs_in relation 73

4.10Processes 74

4.10.1Process 74

4.10.2History 75

4.10.3Process boundary 76

4.10.4Relation of participation 76

4.11Qualities and processes as s-dependent entities 77

4.11.1The ontological square 77

4.11.2The problem of process measurement data 79

4.11.3Why processes do not change 80

4.11.4First approximation to a solution of the problem of process measurement data 82

4.12Processes as dependent entities 83

Mutual dependence among qualities and their parts 86

4.13Process profiles 87

4.13.1Quality process profiles 89

4.13.2Rate process profiles 89

4.13.3Beat process profiles 90

4.14Spatiotemporal region 91

4.15Temporal region 92

zero-dimensional temporal region 93

one-dimensional temporal region 93

4.15.1The precedes relation 93

2References 96