Glossary

Term	Definition	Examples
Physical World	Contains only fundamental particles. No apples, cars, nothing. Those are abstractions in our world models. In physical world there are only groups of fundamental particles that people refer as apples, no apples themselves.
World Model	Representation of the physical world based on abstractions.
Concept	An abstract idea inside of a world model	cat, time, running
Concept of “Entity”	Concept of something that can be acted upon.	apple, word, time, city
Concept of “PhysicalEntity”	An Entity that can refer to something in the physical world. In other words it is an abstract idea that can be acted upon and can refer to something in the physical world.	apple, liquid!!!, water, gas!!!
Concept of “AbstractEntity”	An entity that exists independently of our thoughts about them. Their existence isn’t contingent upon human cognition.  In other words it is an abstract idea that can be acted upon and can not refer to something in the physical world.	number, time, south
Concept of “Instance”	Realisation of an entity. Number is an Entity, “2” is a realisation of a number.	London (instance of a city), Mike (instance of a name), Sudan (instance of a country).