Combining Philosophers

All the ideas for Melvin Fitting, David S. Oderberg and Rita Carter

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48 ideas

2. Reason / D. Definition / 5. Genus and Differentia
'Animal' is a genus and 'rational' is a specific difference [Oderberg]
     Full Idea: The standard classification holds that 'animal' is a genus and 'rational' is a specific difference.
     From: David S. Oderberg (Real Essentialism [2007], 3.5)
     A reaction: My understanding of 'difference' would take it down to the level of the individual, so the question is - which did Aristotle believe in. Not all commentators agree with Oderberg, and Wedin thinks the individual substance is paramount.
Definition distinguishes one kind from another, and individuation picks out members of the kind [Oderberg]
     Full Idea: To define something just means to set forth its limits in such a way that one can distinguish it from all other things of a different kind. To distinguish it from all other things of the same kind belongs to the theory of 'individuation'.
     From: David S. Oderberg (Real Essentialism [2007], 1.4)
     A reaction: I take Aristotle to have included individuation as part of his understanding of definition. Are tigers a kind, or are fierce tigers a kind, and is my tiger one-of-a-kind?
4. Formal Logic / E. Nonclassical Logics / 8. Intensional Logic
If terms change their designations in different states, they are functions from states to objects [Fitting]
     Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3)
     A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough.
Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting]
     Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3.3)
4. Formal Logic / E. Nonclassical Logics / 9. Awareness Logic
Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting]
     Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
     A reaction: [He cites Fagin and Halpern 1988 for this]
4. Formal Logic / E. Nonclassical Logics / 10. Justification Logics
Justication logics make explicit the reasons for mathematical truth in proofs [Fitting]
     Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity.
     From: Melvin Fitting (Intensional Logic [2007], 3.6.1)
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Classical logic is deliberately extensional, in order to model mathematics [Fitting]
     Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics.
     From: Melvin Fitting (Intensional Logic [2007], §1)
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ-abstraction disambiguates the scope of modal operators [Fitting]
     Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □.
     From: Melvin Fitting (Intensional Logic [2007], §3.3)
     A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic.
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
The Aristotelian view is that numbers depend on (and are abstracted from) other things [Oderberg]
     Full Idea: The Aristotelian account of numbers is that their existence depends on the existence of things that are not numbers, ..since numbers are abstractions from the existence of things.
     From: David S. Oderberg (Real Essentialism [2007], 1.2)
     A reaction: This is the deeply unfashionable view to which I am attached. The problem is the status of transfinite, complex etc numbers. They look like fictions to me.
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
Being is substantial/accidental, complete/incomplete, necessary/contingent, possible, relative, intrinsic.. [Oderberg]
     Full Idea: Being is heterogeneous: there is substantial being, accidental being, complete being, incomplete being, necessary being, contingent being, possible being, absolute being, relative being, intrinsic being, extrinsic being, and so on.
     From: David S. Oderberg (Real Essentialism [2007], 5.3)
     A reaction: Dependent being? Oderberg is giving the modern scholastic view. Personally I take 'being' to be univocal, even if it can be qualified in all sorts of ways. I don't believe we actually have any grasp at all of different ways to exist.
7. Existence / E. Categories / 2. Categorisation
Brain lesions can erase whole categories of perception, suggesting they are hard-wired [Carter,R]
     Full Idea: The discovery that a single brain lesion can erase all knowledge of man-made artefacts, or all knowledge of animals, suggests that these categories somehow hard-wired into the brain - that we all have a set of 'memory pigeonholes'.
     From: Rita Carter (Mapping the Mind [1998], p.190)
     A reaction: Presumably something can become 'hard-wired' through experience, rather than from birth. The whole idea of 'hard-wired' seems misleading about the brain. What matters is that the brain physically constructs categories.
8. Modes of Existence / B. Properties / 13. Tropes / b. Critique of tropes
If tropes are in space and time, in what sense are they abstract? [Oderberg]
     Full Idea: If tropes are in space and time, in what sense are they abstract?
     From: David S. Oderberg (Real Essentialism [2007], 4.5)
     A reaction: I take this to be a conclusive objection to claims for any such thing to be abstract. See, for example, Dummett's claim that the Equator is an abstract object.
8. Modes of Existence / C. Powers and Dispositions / 4. Powers as Essence
We need to distinguish the essential from the non-essential powers [Oderberg]
     Full Idea: We need a theory of essence to help us distinguish between the powers that do and do not belong to the essence of a thing.
     From: David S. Oderberg (Real Essentialism [2007], 6.3)
     A reaction: I take this to be a very good reason for searching for the essence of things, though the need to distinguish does not guarantee that there really is something to distinguish. Maybe powers just come and go. A power is essential in you but not in me?
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
Empiricists gave up 'substance', as unknowable substratum, or reducible to a bundle [Oderberg]
     Full Idea: The demise of 'substance' was wholly due to mistaken notions, mainly from the empiricists, by which it was conceived either as an unknowable featureless substratum, or as dispensable in favour of some or other bundle theory.
     From: David S. Oderberg (Real Essentialism [2007], 4.4)
     A reaction: There seems to be a view that the notion of substance is essential to explaining how we understand the world. I am inclined to think that if we accept the notion of essence we can totally dispense with the notion of substance.
9. Objects / D. Essence of Objects / 1. Essences of Objects
Essences are real, about being, knowable, definable and classifiable [Oderberg, by PG]
     Full Idea: Real essences are objectively real, they concern being, they are knowable, they are definable, and they are classifiable.
     From: report of David S. Oderberg (Real Essentialism [2007], 1.4) by PG - Db (ideas)
     A reaction: This is a lovely summary (spread over two pages) of what essentialism is all about. It might be added that they are about unity and identity. The fact that they are intrinsically classifiable seems to mislead some people into a confused view.
9. Objects / D. Essence of Objects / 3. Individual Essences
Nominalism is consistent with individual but not with universal essences [Oderberg]
     Full Idea: Nominalism is consistent with belief in individual essences, but real essentialism postulates essences as universals (quiddities). Nominalists are nearly always empiricists, though the converse may not be the case.
     From: David S. Oderberg (Real Essentialism [2007], 2.1)
     A reaction: This is where I part company with Oderberg. I want to argue that the nominalist/individualist view is more in tune with what Aristotle believed (though he spotted a dilemma here). Only individual essences explain individual behaviour.
9. Objects / D. Essence of Objects / 6. Essence as Unifier
Essentialism is the main account of the unity of objects [Oderberg]
     Full Idea: Real essentialism, more than any other ontological theory, stresses and seeks to explain the unity of objects.
     From: David S. Oderberg (Real Essentialism [2007], 1.3)
     A reaction: A key piece in the jigsaw I am beginning to assemble. If explanation is the aim, and essence the key to explanation, then explaining unity is the part of it that connects with other metaphysics, about identity and so on. 'Units' breed numbers.
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
Essence is not explanatory but constitutive [Oderberg]
     Full Idea: Essence is not reducible to explanatory relations, ...and fundamentally the role of essence is not explanatory but constitutive.
     From: David S. Oderberg (Real Essentialism [2007], 3.1)
     A reaction: Effectively, this asserts essence as part of 'pure' metaphysics, but I like impure metaphysics, as the best explanation of the things we can know. Hence we can speculate about constitution only by means of explanation. Constitution is active.
9. Objects / D. Essence of Objects / 9. Essence and Properties
Properties are not part of an essence, but they flow from it [Oderberg]
     Full Idea: A substance is constituted by its essence, and properties are a species of accident. No property of a thing is part of a thing's essence, though properties flow from the essence.
     From: David S. Oderberg (Real Essentialism [2007], 7.2)
     A reaction: I'm not sure I understand this. How can you know of something which has no properties? I'm wondering if the whole notion of a 'property' should be eliminated from good metaphysics.
9. Objects / D. Essence of Objects / 15. Against Essentialism
Could we replace essence with collections of powers? [Oderberg]
     Full Idea: Why not do away with talk of essences and replace it with talk of powers pure and simple, or reduce essences to collections of powers? But then what unites the powers, and could a power be lost, and is there entailment between the powers?
     From: David S. Oderberg (Real Essentialism [2007], 6.3)
     A reaction: [He cites Bennett and Hacker 2003 for this view] The point would seem to be that in addition to the powers, there are also identity and unity and kind-membership to be explained. Oderberg says the powers flow from the essence.
9. Objects / F. Identity among Objects / 8. Leibniz's Law
Leibniz's Law is an essentialist truth [Oderberg]
     Full Idea: Leibniz's Law is an essentialist truth.
     From: David S. Oderberg (Real Essentialism [2007], 1.1)
     A reaction: That is, if two things must have identical properties because they are the same thing, this is because those properties are essential to the thing. Otherwise two things could be the same, even though one of them lacked a non-identifying property.
10. Modality / B. Possibility / 4. Potentiality
Bodies have act and potency, the latter explaining new kinds of existence [Oderberg]
     Full Idea: The fundamental thesis of real essentialism is that every finite material body has a twofold composition, being a compound of act and potency. ...Reality can take on new kinds of existence because there is a principle of potentiality inherent in reality.
     From: David S. Oderberg (Real Essentialism [2007], 4.1)
     A reaction: I take from this remark that the 'powers' discussed by Molnar and other scientific essentialists is roughly the same as 'potentiality' identified by Aristotle.
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
Realism about possible worlds is circular, since it needs a criterion of 'possible' [Oderberg]
     Full Idea: Any realist theory of possible worlds will be circular in its attempt to illuminate modality, for there has to be some criterion of what counts as a possible world.
     From: David S. Oderberg (Real Essentialism [2007], 1.1)
     A reaction: Seems right. At the very least, if we are going to rule out contradictory worlds as impossible (and is there a more obvious criterion?), we already need to understand 'impossible' in order to state that rule.
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Definite descriptions pick out different objects in different possible worlds [Fitting]
     Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally.
     From: Melvin Fitting (Intensional Logic [2007], 3.4)
     A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others.
Necessity of identity seems trivial, because it leaves out the real essence [Oderberg]
     Full Idea: The necessity of identity carries the appearance of triviality, because it is the eviscerated contemporary essentialist form of a foundational real essentialist truth to the effect that every object has its own nature.
     From: David S. Oderberg (Real Essentialism [2007], 1.1)
     A reaction: I like this. Writers like Mackie and Forbes have to put the 'trivial' aspects of essence to one side, without ever seeing why there is such a problem. Real substantial essences have necessity of identity as a side-effect.
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Rigid designation has at least three essentialist presuppositions [Oderberg]
     Full Idea: The rigid designator approach to essentialism has essentialist assumptions. ..The necessity of identity is built into the very conception of a rigid designator,..and Leibniz's Law is presupposed...and necessity of origin presupposes sufficiency of origin.
     From: David S. Oderberg (Real Essentialism [2007], 1.1)
     A reaction: [compressed. He cites Salmon 1981:196 for the last point] This sounds right. You feel happy to 'rigidly designate' something precisely because you think there is something definite and stable which can be designated.
12. Knowledge Sources / B. Perception / 5. Interpretation
Sense organs don't discriminate; they reduce various inputs to the same electrical pulses [Carter,R]
     Full Idea: Despite their variety, each sense organ translates its stimulus into electrical pulses; rather than discriminating one type of input from another, the sense organs actually make them more alike.
     From: Rita Carter (Mapping the Mind [1998], p.174)
     A reaction: An illuminating observation, which modern 'naïve realists' should bear in mind. Secondary qualities are entirely unrelated to the nature of the input, and are merely 'what the brain decides to make of it'. Discrimination is in our neurons.
The recognition sequence is: classify, name, locate, associate, feel [Carter,R, by PG]
     Full Idea: The sequence of events in the brain for perceptual recognition is first identifying a rough class for the object, then a name, then a location, then some associations, and finally an emotion.
     From: report of Rita Carter (Mapping the Mind [1998], p.181) by PG - Db (ideas)
     A reaction: This seems to be one of those places where neuro-science trumps philosophy. You can't argue with empirical research, so philosophical theories had better adapt themselves to this sequence. The big modern discovery is the place of emotion in recognition.
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
There seems to be no dividing line between a memory and a thought [Carter,R]
     Full Idea: It has become clear from research that there is no clear dividing line between a memory and a thought.
     From: Rita Carter (Mapping the Mind [1998], p.308)
     A reaction: This always struck me as an obvious criticism of Descartes, when he claimed that memory was not an essential part of the 'thinking thing'. How can you think or understand without memory of the different phases of your thoughts? No memory, no mind!
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
No one knows if animals are conscious [Carter,R]
     Full Idea: No one knows if animals are conscious.
     From: Rita Carter (Mapping the Mind [1998], p.155)
     A reaction: This is a report from the front line of brain research, and should be born in mind when over-confident people make pronouncements about this topic. It strikes me as important to grasp that animals MIGHT not be conscious.
15. Nature of Minds / A. Nature of Mind / 8. Brain
Pain doesn't have one brain location, but is linked to attention and emotion [Carter,R]
     Full Idea: Scans show there is no such thing as a pain centre; pain springs mainly from the activation of areas associated with attention and emotion.
     From: Rita Carter (Mapping the Mind [1998], p. 12)
     A reaction: Most brain research points to the complex multi-layered nature of experiences that were traditionally considered simple. We can be distracted from a pain, and an enormous number of factors can affect our degree of dislike of a given pain.
Proper brains appear at seven weeks, and neonates have as many neurons as adults do [Carter,R]
     Full Idea: The main sections of the brain, including the cerebral cortex, are visible within seven weeks of conception, and by the time the child is born the brain contains as many neurons - about 100 billion - as it will have as an adult.
     From: Rita Carter (Mapping the Mind [1998], p. 17)
     A reaction: Of interest in the abortion debate, and also in thinking about personal identity. However, it seems clear that the number of connections, rather than neurons, is what really matters. A small infant may well lack personal identity.
In primates, brain size correlates closely with size of social group [Carter,R]
     Full Idea: Brain size in primates is closely associated with the size of the social group in which the animal lives.
     From: Rita Carter (Mapping the Mind [1998], p.257)
     A reaction: Intriguing. Humans can have huge social groups because of language, which suggests a chicken-or-egg question. Language, intelligence and size of social group must have expanded together in humans.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / c. Parts of consciousness
Consciousness involves awareness, perception, self-awareness, attention and reflection [Carter,R]
     Full Idea: Awareness, perception, self-awareness, attention and reflection are all separate components of consciousness, and the quality of our experience varies according to which and how many of them are present.
     From: Rita Carter (Mapping the Mind [1998], p.300)
     A reaction: Philosophers like to emphasise 'qualia' and 'intentionality'. This remark slices the cake differently. 'Attention' is interesting, dividing consciousness into two areas, with some experience fading away into the darkness. Hume denied self-awareness.
15. Nature of Minds / B. Features of Minds / 1. Consciousness / e. Cause of consciousness
There is enormous evidence that consciousness arises in the frontal lobes of the brain [Carter,R]
     Full Idea: A huge volume of evidence suggests that consciousness emerges from the activity of the cerebral cortex, and in particular from the frontal lobes.
     From: Rita Carter (Mapping the Mind [1998], p.298)
     A reaction: Dualists must face up to this, and even many physicalists have a rather vague notion about the location of awareness, but we are clearly homing in very precise physical substances which have consciousness as a feature.
15. Nature of Minds / B. Features of Minds / 5. Qualia / a. Nature of qualia
Normal babies seem to have overlapping sense experiences [Carter,R]
     Full Idea: Connections in a baby's brain probably give the infant the experience of 'seeing' sounds and 'hearing' colours - which occasionally continues into adulthood, where it is known as 'synaesthesia'.
     From: Rita Carter (Mapping the Mind [1998], p. 19)
     A reaction: A fact to remember when discussing secondary qualities, and the relativism involved in the way we perceive the world. If you have done your philosophy right, you shouldn't be surprised by this discovery.
15. Nature of Minds / B. Features of Minds / 7. Blindsight
In blindsight V1 (normal vision) is inactive, but V5 (movement) lights up [Carter,R]
     Full Idea: Scans show that a sub-section of the visual cortex called V5 - the area that registers movement - lights up during blindsight, even though V1 - the primary sensory area that is essential for normal sight - is not active.
     From: Rita Carter (Mapping the Mind [1998], p.307)
     A reaction: The whole point of blindsight is to make us realise that vision involves not one module, but a whole team of them. The inference is that V1 involves consciousness, but other areas of the visual cortex don't.
17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique
Out-of-body experiences may be due to temporary loss of proprioception [Carter,R]
     Full Idea: Out-of-body experiences may be due to temporary loss of proprioception.
     From: Rita Carter (Mapping the Mind [1998], p.187)
     A reaction: This is only a speculation, but it is an effect which can be caused by brain injury, and dualists should face the possibility that this evidence (prized by many dualists) can have a physical explanation.
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
Scans of brains doing similar tasks produce very similar patterns of activation [Carter,R]
     Full Idea: The pattern of brain activation during, say, a word retrieval task is usually similar enough among the dozen or so participants who typically take part in such studies for their scans to be overlaid and still show a clear pattern.
     From: Rita Carter (Mapping the Mind [1998], p. 17)
     A reaction: This doesn't surprise me, though it could be interpreted as supporting type-type identity, or as supporting functionalism. Armstrong and Lewis endorse a sort of reductive functionalism which would fit this observation.
Thinking takes place on the upper side of the prefrontal cortex [Carter,R]
     Full Idea: The nuts and bolts of thinking - holding ideas in mind and manipulating them - takes place on the upper side of the prefrontal cortex.
     From: Rita Carter (Mapping the Mind [1998], p.312)
     A reaction: Keep this firmly in view! Imagine that the skull is transparent, and brain activity moves in waves of colour. Dualism would, in those circumstances, never have even occurred to anyone.
18. Thought / A. Modes of Thought / 3. Emotions / a. Nature of emotions
Babies show highly emotional brain events, but may well be unaware of them [Carter,R]
     Full Idea: Babies show emotion dramatically, but the areas of the brain that in adults are linked to the conscious experience of emotions are not active in newborn babies. Such emotions may therefore be unconscious.
     From: Rita Carter (Mapping the Mind [1998], p. 19)
     A reaction: Traditionally, 'unconscious emotion' is a contradiction, but I think we should accept this new evidence and rethink the nature of mind. Not only might emotion be non-conscious, but we should even consider that rational thinking could be too.
18. Thought / A. Modes of Thought / 3. Emotions / g. Controlling emotions
The only way we can control our emotions is by manipulating the outside world that influences them [Carter,R]
     Full Idea: We try to manipulate our emotions all the time, but all we are doing is arranging the outside world so it triggers certain emotions - we cannot control our reactions directly.
     From: Rita Carter (Mapping the Mind [1998], p.155)
     A reaction: This seems to me to throw a very illuminating light on a huge amount of human behaviour, such as going to the cinema or listening to music. The romantic movement encouraged direct internal manipulation. Compare sex fantasies with viewing pornography.
18. Thought / A. Modes of Thought / 5. Rationality / c. Animal rationality
A frog will starve to death surrounded by dead flies [Carter,R]
     Full Idea: A frog will starve to death surrounded by dead flies.
     From: Rita Carter (Mapping the Mind [1998], p.195)
     A reaction: A nice warning against assuming that rationality is operating when a frog feels hungry and 'decides' to have lunch. We should take comfort from the fact that humans are NOT this stupid, and philosophers should try to accurately describe our gift.
22. Metaethics / C. The Good / 3. Pleasure / d. Sources of pleasure
The 'locus coeruleus' is one of several candidates for the brain's 'pleasure centre' [Carter,R]
     Full Idea: Noradrenaline is an excitatory chemical that induces physical and mental arousal and heightens mood. Production is centred in an area of the brain called the locus coeruleus, which is one of several candidates for the brain's 'pleasure' centre.
     From: Rita Carter (Mapping the Mind [1998], p. 30)
     A reaction: It seems to me very morally desirable that people understand facts of this kind, so that they can be more objective about pleasure. Pleasure is one cog in the machine that makes a person, not the essence of human life.
26. Natural Theory / A. Speculations on Nature / 3. Natural Function
Essence is the source of a thing's characteristic behaviour [Oderberg]
     Full Idea: In the traditional terminology, function follows essence. Essence just is the principle from which flows the characteristic behaviour of a thing.
     From: David S. Oderberg (Real Essentialism [2007], 2.1)
     A reaction: Hence essence must be identified if the behaviour is to be explained, and a successful identification of essence is the terminus of our explanations. But the essences must go down to the micro-level. Explain non-characteristic behaviour?
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
What makes Parmenidean reality a One rather than a Many? [Oderberg]
     Full Idea: Even if there were no multiplicity in unity - only a Parmenidean 'block' - still the question would arise as to what gave the amorphous lump its unity; by virtue of what would it be one rather than many?
     From: David S. Oderberg (Real Essentialism [2007], 3.1)
     A reaction: Which is prior, division or unification? If it was divided, he would ask what divided it. One of them must be primitive, so why not unity? If one big Unity is primitive, why could not lots of unities be primitive? Etc.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
The real essentialist is not merely a scientist [Oderberg]
     Full Idea: It is incorrect to hold that the job of the real essentialist just is the job of the scientist.
     From: David S. Oderberg (Real Essentialism [2007], 1.3)
     A reaction: Presumably scientific essentialism, while being firmly a branch of metaphysics, is meant to clarify the activities of science, and thereby be of some practical use. You can't beat knowing what it is you are trying to do.
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / e. Anti scientific essentialism
The reductionism found in scientific essentialism is mistaken [Oderberg]
     Full Idea: The reductionism found in scientific essentialism is mistaken.
     From: David S. Oderberg (Real Essentialism [2007], 1.4)
     A reaction: Oderberg's point is that essence doesn't just occur at the bottom of the hierarchy of kinds, but can exist on a macro-level, and need not be a concealed structure, as we see in the essence of a pile of stones.