There are two ways in which things exist.
They may have objective existence ─ exist outside of the self ─ and thus in principle be detectable by the senses.
Or they may be concepts, abstractions, generalizations, fictions, imaginings, delusions, hallucinations, false information, and so on, which only exist as part of an individual's mentation.
The rest I may wish to modify later, but off the top of my head ─
The halfway house between the two is the generalization. An idealized quality like 'justice' only exists as a concept in a brain, but particular real cases of conduct between humans may still be instances of justice.
And while you'll never find 'a chair' in reality (an abstraction, a mental construct), you may find 'this chair' or 'that chair' quite easily.
In the same way, abstract concepts with no external referent, as with 'mathematical objects' like 1, 2, 3, may have instantiations in reality ─ one elephant, two ducks, three blind mice.
There are no instantiations of -1, -2, -3, since they're all relative to prior situations, hence conceptual. And no instantiations of pi, √2 or other real numbers, which require an infinite precision not found in nature.
Whether instantiations of some complex numbers can properly said to be found in eg magnetic fields I'll leave to others more familiar with the material.
They may have objective existence ─ exist outside of the self ─ and thus in principle be detectable by the senses.
Or they may be concepts, abstractions, generalizations, fictions, imaginings, delusions, hallucinations, false information, and so on, which only exist as part of an individual's mentation.
The rest I may wish to modify later, but off the top of my head ─
The halfway house between the two is the generalization. An idealized quality like 'justice' only exists as a concept in a brain, but particular real cases of conduct between humans may still be instances of justice.
And while you'll never find 'a chair' in reality (an abstraction, a mental construct), you may find 'this chair' or 'that chair' quite easily.
In the same way, abstract concepts with no external referent, as with 'mathematical objects' like 1, 2, 3, may have instantiations in reality ─ one elephant, two ducks, three blind mice.
There are no instantiations of -1, -2, -3, since they're all relative to prior situations, hence conceptual. And no instantiations of pi, √2 or other real numbers, which require an infinite precision not found in nature.
Whether instantiations of some complex numbers can properly said to be found in eg magnetic fields I'll leave to others more familiar with the material.
