curs 9 niveluri si reductie vs
TRANSCRIPT
Niveluri si reductie vs. emergenta
1. Niveluri
In explicarea cognitiei, e tipic pentru filosofi sa gandeasca in termeni de niveluri
micro- (nivelul neuronal) si macro (nivelul mental). Sunt 2 tipuri de interactiuni:
intraniveluri (interactiuni orinzontale) adica interactiuni intre componentele la acelasi
nivel, si interniveluri (interactiuni verticale) adica interactiuni intre niveluri. Daca
“substante” implica interactiuni orizontale (adica uniunea lor), niveluri implica relatii
ontologice sau epistemologice verticale (vertical referindu-se la ontologic,
organizational, metodologic, de analiza sau epistemologic). Sunt deci niveluri
ontologice, organizationale (mecanisme sau sisteme), epistemologice sau de descries
au analiza.
2. Reduction and emergence
Istoria emergentei1 este destul de complicata pentru ca are multe interpretari.2
Emergence involves certain vertical relationships between low-level and high-level
properties. The notion of “levels” implies the concept of emergence. When we talk
about reduction or emergence, we need to specify what is reduced to what or what
emerges from what. We can reduce one property or level to another or one property or
one level can emerge from another.
On the one side, we can relate reduction and epistemological levels/properties
and epistemological emergence to identity theory and even to eliminative materialism.
(Week 3)
According to van Gulick, emergence is “’Xs are more than just Ys’ and that
‘Xs are something over and above Ys.’” He distinguishes as classes of emergence
between properties and causal powers or forces. (van Gulick 2001) The emergent
features go beyond the features of parts from which they emerge (p. 16) and it can be
categorized as “metaphysical emergence” (it refers to the relation between real things)
or “epistemic emergence” (cognitive explanatory relations about real world items).
What does “over and above” or “emergent features go beyond the features of parts”
1 Kim wrote “Since around 1990, the idea of emergence has been making a big comeback, from decades of general neglect and disdain on the part of mainstream analytic philosophy.” (Kim 2006, p. 547) 2 Kim again: “‘Emergence’ is very much a term of philosophical trade; it can pretty much mean whatever you want to mean…” (Kim 2006, p. 548)
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mean? Earlier than van Gulick, there were other people insisting upon the difference
between ontological and epistemological emergence considering that people many
times conflate them. (Silberstein and McGeever 1999; O’Connor and Wong 2002)
Emergence has the same properties as nonreductive physicalism: distinctness
and dependence. (Crane 2001) It involves the whole-part relationships. Now, some
properties are simply combinations of parts at the same level, as it were. The
emergent properties are different from the sum of their parts; they presuppose novelty.
It is quite difficult to define this “novelty”. In Crane’s definition, the novel properties
of an object would be “those determinable properties whose determinates are not had
by all of the object’s parts.” (p. 8) From this perspective, surface colour and wetness
are novel properties. However, in order to distinguish emergent properties from
reductive properties, novelty is not enough. According to Crane, a stronger notion of
emergence conceives of it as a property of a whole with powers that are not related to
the powers of its parts. This strong notion of emergence denies that the emergent
properties of a whole are supervenient upon the properties of its parts. A dependent
property implies that the properties of the whole supervene on the properties of its
parts. Therefore, for Crane emergence is strongly related to the supervenience of a
whole’s properties on the properties of its parts. (Crane 2001, p. 9) However, for an
emergentist, such properties would be “over and above" the physical properties.
One essential dichotomy is the difference between epistemological and
ontological emergence. People many times conflate them. (Silberstein and McGeever
1999; O’Connor and Wong 2002)
2.1 Ontological emergence
According to van Gulick, metaphysical emergence has three forms: (1) Specific value
emergence (“The whole and its parts have features of the same kind but have different
specific subtypes or values of that kind.” He offers the example of a bronze statue and
the molecular parts with common property, the mass. (2) Modest kind emergence:
“The whole has features that are different in kind from those of its parts …”
(Examples are color and life.) (3) Radical kind emergence: “The whole has features
that are both 1) Different in kind from those had by its parts and 2) Of kind whose
nature and existence is not necessitated by the features of its parts, their mode of
combination and the law-like regularities governing the features of its parts.” (van
Gulick 2001, p. 17)
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According to O’Connor and Wong, there are different versions of such
emergence but the most common versions are as following:
Predictive: Emergent properties are systemic features of complex systems which could not be predicted
(practically speaking; or for any finite knower; or for even an ideal knower) from the standpoint of a
pre-emergent stage, despite a thorough knowledge of the features of, and laws governing, their parts.
Irreducible-Pattern: Emergent properties and laws are systemic features of complex systems governed
by true, lawlike generalizations within a special science that is irreducible to fundamental physical
theory for conceptual reasons. The macroscopic patterns in question cannot be captured in terms of the
concepts and dynamics of physics. (O’Connor and Wong 2002)
The authors consider that epistemological emergence has applications in particular
sciences mainly regarding the relationship between macro-and micro-levels. In their
opinion ontological emergence is equivalent to what they call “supervenience
emergentism”.
Even if some of proponents of ontological emergence consider that the world
is composed by fundamental entities, they maintain the layered view of nature.
Ontologically emergent properties are not determined or reducible to basic
properties.3 However, ontological emergence is highly controversial and there are not
too many philosophers who believe in the existence of ontological levels or
ontological emergence.4
If we are trying to relate the notions of levels to van Gulick’s view on
emergence, we can say that ontological levels would be correlated with radical
emergence, organizational levels with modest emergence, and levels of analysis with
specific value emergence. The last two levels can be both divided into weak and
strong epistemic emergence. The problem is that if we accept ontologically different
levels and radical emergence then we collapse into Cartesian dualism that is rejected
by the majority of philosophers. Nevertheless, for saving the phenomena some
philosophers (mainly non-reductive materialists) knew that rejecting Cartesian
3 One classical example of ontological emergence is quantum mechanics. (Silberstein and McGreever 1999)4 Ontological emergence is applied not only to the mind-brain topic but also to the macro-micro levels of reality. Authors like Prigojine and R. B. Laughlin -both Nobel laureates- assert the irreducibility of certain macroscopic properties to micro-properties. In this sense, Prigojine introduces the “dissipative structure” of non-equilibrium thermodynamics and Laughlin brings in the “protected” properties (like crystalline state) of a high level of reality insensitive to microscopic properties. (O’Connor and Wong, 2002)
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dualism involves the acceptance of some anomalies. Therefore they consider the
human being as a limited entity that has limited knowledge (McGinn) or they seek
refuge under the ontology-epistemology distinction (with levels of analysis and the
corresponding epistemic emergence, weak and strong) or they introduce
organizational levels (related to layered view of nature).
For Chalmers, a strong emergent property is one in which “the high-level
phenomenon arises from a low-level domain, but truths concerning that phenomenon
are not deducible even in principle from truths in the low-level domain.” (Chalmers
2006) If the strong emergent phenomena cannot be deducible from the laws of
physics, for instance, then we need new laws of nature for explaining such
phenomena. The only known phenomenon that cannot be explained by physical laws
is consciousness. The examples for supporting this idea are those of the colorblind
scientist and zombies. However, consciousness is correlated with or supervenes on
physical, neural states.
2.2 Epistemological emergence
More complex is the status of epistemic emergence (weak and strong). For Silberstein
and McGeever, Stephan, van Gulick, O’Connor and Wong, Chalmers, and Kim,
epistemic emergence is related to our incapacity to explain and predict such a
property of a whole system in terms of its parts. However, the property of the whole is
determined by the properties of parts. For van Gulick, epistemic emergence is
subjective and there are weak and strong emergences that characterize predictive and
explanatory emergence and representational emergence. For Silberstein and
McGeever, we can analyze epistemological emergence only from a viewpoint given
by the relationship between human knowledge and simple or complex systems. This
concerns the functional or descriptive/analysis of emergence. A property of an entity
is an epistemological emergent if that property is determined to or deducible from the
intrinsic properties of the fundamental entities that compose the object. However, it is
difficult to explain or predict such a property in terms of its fundamental constituents.
(Silberstein and McGeever 1999) “Epistemologically emergent properties are novel
only at a level of description.” (Silberstein and McGeever 1999, p. 186)
For Chalmers, a high-level phenomenon represents a weak emergence in
relation to a low-level domain when that phenomenon is “unexpected” in accord with
the laws or principles from low-level area. By “unexpected” he means that emergent
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properties are somehow deductible from low-level properties (with initial conditions).
Examples of such emergence are “the game of life”, connectionist networks,
evolution (for intelligent creatures) and high-level patterns in cellular automata.
Chalmers’ definition of weak emergence is (a) high-level properties are those
properties of a system that are not possessed by any of its part (b) deductibility
without reducibility.
A more complicated investigation of the notion of emergence is made by
Achim Stephan. (Stephen 2002, 1998) He distinguishes several theories of
emergence: weak, synchronic, and diachronic emergence. According to weak
emergentism, the properties of a system are emergent if they belong to the system as a
whole, but not to the parts of that system. This kind of emergentism is equivalent to
property reductionism because the emergent structures are explainable and completely
definable in terms of the combination of parts already defined. The system as a whole
is the sum of parts plus the organization or cooperation of parts. A typical example of
weak emergentism is connectionist networks but this emergentism is also applicable
to the theories of self-organization and artificial intelligence. (Stephen 2002, 1998)
According to Stephen (2002), weak emergentism has three characteristics. The first is
physical monism: all entities, properties and structures emerge from certain
fundamental physical parts. The second characteristic consists in systemic properties.
There are two classes of properties: the properties that the parts of the system also
have (e.g., velocity) and the properties that do not belong to the parts of the system
(e.g., pain). The laws properties represent the second feature. The third feature is
synchronic determination (or mereological supervenience), and reflects the
relationship between basic structure and emergent properties. The last properties
depend on the parts’ properties and their arrangement. (Chalmers 2006)
The main characteristics of diachronic properties are the novelty and the
unpredictability of the system that evolves. (Stephen 2002, 1998) The difference
between weak and diachronic emergence is the unpredictability of properties. The
difference between diachronic and synchronic emergence is the irreducibility of
properties. Moreover, if one property or entity has not existed before and suddenly
comes into existence, it means that the property or entity is diachronically new.
Synchronic novelty is time independent. (Scholz 2004, p. 2) These two kinds of
irreducibility produce either downward causation or epiphenomenalism. An
irreducible property means one that (a) does not follow from the behavior of the
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system’s parts that has this property and (b) does not follow from the behavior of the
system’s parts in constellations simpler than the system. Qualia are the typical cases
of synchronic emergent properties.
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