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“Coleridge observes that all men are born Aristotelians or Platonists.

“Coleridge observes that all men are born Aristotelians or Platonists. The latter feel that classes, orders, and genres are realities ; the former, that they are generalizations .

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“Coleridge observes that all men are born Aristotelians or Platonists.

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  1. “Coleridge observes that all men are born Aristotelians or Platonists. The latter feel that classes, orders, and genres are realities; the former, that they are generalizations. For the latter, language is nothing but an approximative set of symbols; for the former, it is the map of the universe. The Platonist knows that the universe is somehow a cosmos, an order; that order, for the Aristotelian, can be an error or a fiction of our partial knowledge. Across the latitudes and the epochs, the two immortal antagonists change their name and language: one is Parmenides, Plato, Spinoza, Kant, Francis Bradley the other, Heraclitus, Aristotle, Locke, Hume, William James.”

  2. Truth and Reality

  3. Truth and Reality

  4. “TRUTH and REALITY”the neuropsychology of belief Neil GreenbergUniversity of TennesseeKnoxville, TN USA Knowing … noesis … agnosia … hypergnosia … “feeling of knowing” … TOT phenomena Truth and Reality

  5. WHAT is BELIEF? No precise, agreed upon definition is available, so: Belief is the psychological state in which an individual is more-or-less confident in the validity of a proposition. (confidence can translate into biological fitness) Confidence is based on real or perceived validity – which can be more-or-less internal (limited generalizability; eg, individual) or external(broad generalizablity; eg, population) Truth and Reality

  6. ALTERNATIVE CONCEPTS of BELIEF? “BELIEFS” are useful entities: cerebral representations of relationships – Jerry Fodor “BELIEFS” are not the neural representations they seem to be but they are a valuable scaffold for the next stage in research. –Stephen Stich “BELIEFS” will be wholly superseded by emerging understandings of the way the brain represents the variables of the world we have to cope with – Paul & Patricia Churchland Truth and Reality

  7. PROBLEMS? “BELIEFS” may not be valid constructs, but looking for them is very productive. Treating a person (or a computer) AS IF it had beliefs is powerfully predictive This understanding of belief was nicknamed the intentional stance ny Daniel Dennett: belief based explanations may not be reducible to those based on fundamental neuroscience although both may be explanatory at their own level. Truth and Reality

  8. TOP-DOWN BELIEF? TOP DOWN: at several levels cognitive neuroscience has investigated, expectations are reconciled with experience. IF expectations are not met, a subclinical stress response recruits or mobilizes or enables alternative inputs; lateral inhibition may be suppressed to provide access to a broader range of stimuli that might bear on the mismatch. Truth and Reality

  9. TOP-DOWN BELIEF? Decision theory proposes that humans and animals decide what to do in a given situation by assessing the relative value of each possible response “gain a monkey can expect to realize from an eye-movement response modulates the activity of neurons in the lateral intraparietal area, an area of primate cortex that is thought to transform visual signals into eye-movement commands. Platt (et al. 1999) show that the activity of these neurons is sensitive to the probability that a particular response will result in a gain.” (reward) Truth and Reality

  10. BOTTON-UP BELIEF? BOTTOM UP: a classical conditioning paradigm applied to the spinal cord can induce alterations in spinal reflexes of long duration –Durcovic 1985 Even the simplest, monosynaptic spinal reflexes can learn and store memory traces in operant conditioning experiments, as has been shown in the ingenious studies by Wolpaw and his group (Wolpaw 1987; Wolpaw and Carp 1993). Truth and Reality

  11. BOTTON-UP BELIEF? BOTTOM UP: Visual cortex is traditionally viewed as a hierarchy of neural feature detectors, with neural population responses being driven by bottom-up stimulus features Comparing expectation versus error, data can be explained by predictive coding [expectation + mismatch] but not by feature detection models, even when the latter are augmented with attentional mechanisms. Thus, population responses in the ventral visual stream appear to be determined by feature expectation and surprise rather than by stimulus features per se. (Tobias Egner et al at Duke in 2010 studying a categorfy-selective visual area (fusiform face area)) . Truth and Reality

  12. We derive our beliefs… “…through argument and experience. Argument brings conclusions and compels us to concede them, but does not cause certainty nor remove the doubts in order that the mind may remain at rest in truth, unless this is provided by experience.” Roger Bacon (1268)

  13. The unknown versus the unknowable Knowledge is a correspondence between what is to be known and some attribute of the knowing mind: But ALL perception, ALL cognition, and ALL action are selective representations of experience: ABSTRACTIONS … … reducing data by congenital, developmental, and experiential circumstances to the least knowable bit that will serve our biological FITNESS… 

  14. The unknown versus the unknowable On Exactitude in Science . . . In that Empire, the Art of Cartography attained such Perfection that the map of a single Province occupied the entirety of a City, and the map of the Empire, the entirety of a Province. In time, those Unconscionable Maps no longer satisfied, and the Cartographers Guilds struck a Map of the Empire whose size was that of the Empire, and which coincided point for point with it. … In the Deserts of the West, still today, there are Tattered Ruins of that Map, inhabited by Animals and Beggars; in all the Land there is no other Relic of the Disciplines of Geography --Borges

  15. SOURCES of BELIEF These processes are centered in the brain and involve subjecting units of incoming information (percepts) to two complementary “tests” (reality-testing and theorizing). These tests bear a striking resemblance to the two prominent philosophical views of “truth,” correspondenceand coherence.

  16. HOW IS BELIEF ESTABLISHED? • Empiricism and Reality-Testing • data-based, induction-driven • PERCEPTS CORRESPOND to reality • Rationalism and Story-Telling • theory-based, deduction-driven • PERCEPTS COHERE with each other Truth and Reality

  17. COHERENCE is COMFORTING “A world that can be explained even with bad reasons is a familiar world. But on the other hand, in a universe divested of illusions and lights, man feels an alien, a stranger. . . .” A “predictable” world is much less stressful Albert Camus

  18. correspondence and coherenceevidence and theory past and future These two domains – one rooted in the past, the other in imagination– collaborate in creating a “sense of confidence in a belief,” not least, one’s self. Increasing the degree of confidence in the validity of a belief enhances biological fitness … ecologically, there is an “optimal” cost/benefit ratio for a given level of confidence Organisms often continue to try to increase confidence depending on perceived urgency and resources and can become addicted (search and discovery is pleasurable) Truth and Reality

  19. RECALLED IMAGINATION, IMAGINED MEMORIES Episodic memory and plausible personal imagination share a consistentnetwork of associated brain regions connected in a distributed network of neural modules …some of which may support self-schemaand familiarity processes, and contribute to the brain's abilityto distinguish real from imaginary memories. Hassabis et al., 2007 Truth and Reality

  20. An Aside on Chance and Necessity: the intrinsic imperfection of knowledge Our inner world, umwelt, of necessity provides an abstraction at best. • Experience and neuroplasticity • Neuronal activity recycling time • Lateral inhibition … extrapolation and interpolation Truth and Reality

  21. evidence and theorycorrespondence and coherence … the biological value of truth is important in so far as … (1) the search for truth exercises and enlarges our competence(play, the scientist in the crib)and (2) approximating the truth may provide a biological advantage (better maps) Scaffolding? Successive approximations? Zeno’s paradox? Truth and Reality

  22. To ACT with CONFIDENCEis biologically significant Much of our behavior is structured by the possession and pursuit of confidence in the validity of our beliefs – their “truth.” The neuroethology of consciousness and its dysfunctions have helped us identify the manner in which correspondence and coherence function and converge to create a sense of more-or-less doubt or confidence in the veracity of a belief.

  23. ACTIONS are based on BELIEFS. We seek “TRUTH” because we can never be too confident. It is BIOLOGICALLY ADAPTIVE in that it meets a NEED and enhances FITNESS Such NEEDS range from physiology (health) through fitness (“self actualization”), and meeting them is the principal business of life. CONFIDENCE can be anxiolytic: real or perceived needs that are not met evoke more-or-less of the STRESS RESPONSE, the physiology of which selectively activates brain circuits which also energize MOTIVATION

  24. DEEP ethology of belief • DEVELOPMENT: change within a lifespan -- the scientist in the crib and accumulating experiences • ECOLOGY: meeting needs in the environment -- dynamic balance, and meeting needs, real or perceived • EVOLUTION: Change between generations -- What elements of belief are fixed and which are flexible? • PHYSIOLOGY: Homeostasis, coping with needs; stress, orchestrating the cerebral symphony; dynamic tension of tradition and innovation

  25. DEVELOPMENT Infants are “scientists in the crib,” always developing and testing, accepting or rejecting, hypotheses about the nature of our environments and how best to control them. It is a necessary stage of our cognitive development that makes learning possible . . and it is the beating heart of the scientific method. (if we can hold onto the “freshness” of perceptions) Truth and Reality

  26. Our brains are formed by the EPIGENETIC interaction of organism and environment:all percepts are modified by those that came before.

  27. We see the world not as it is, But as we are . . . (Talmud) Truth and Reality

  28. We see the world not as it is, But as we are . . . Jacob’s Ladder connects earth and heaven, the real and the ideal Truth and Reality

  29. We see the world not as it is, But as we are . . . Truth and Reality

  30. BRAIN EVOLUTIONexcavating the paleopsychology of our species: "The Brain of Man has not abandoned it's ancient animal foundations, it has built upon them . . . . But it has also reconstructed them as the shifting earth beneath dictates . . . . We have done the best possible in the landscape in which we have found ourselves with the raw materials we have inherited." (Prolegomena to a Study of Mind, 1973, ch. 42)

  31. “The mind consists of countless layers of overlapping, interconnected nets, each sharing millions of knots called neurons, and deployed to catch and control whatever experiences will advance our fitness -- our relative success in the meeting of needs to survive and thrive. No single net can catch much of anything of great use, each catches fragments at best.” –Art & Organism

  32. PHYSIOLOGY STRESS RESPONSES are evoked by REAL or PERCEIVED challenges to an organism’s ability to meet its needs SUBCLINCAL STRESSis evoked by modest challenges to homeostasis, including COGNITIVE DISSONANCE, an apparent mismatch between internal perceptions and external reality; challenges to the narrative that confers biologically valuable confidence.

  33. CORRESPONDENCE THE POWER OF REALITY- TESTING We confirm and establish confidence in CORRESPONDENCE (the validity of experiences) at every level, from spinal reflexes through thoughtful cognition. Experiences we are confident are real but which challenge theory is the key method of enlarging our worlds. Establishing validity is a key element of learning. Truth and Reality

  34. COHERENCE THE POWER OF THEORY We confirm and establish confidence in COHERENCE by assessing the validity of component percepts and their complexity. Expectations exist at many levels, from habituation and sensitization of sensory receptors through the most elaborate flights of philosophy. Truth and Reality

  35. We NEED theory La theorie seule peut faire surgir et developper l'esprit d'invention" (Without theory, practice is no more than the routine given by habit. Theory alone can bring forth and develop the spirit of invention) Louis Pasteur

  36. NARRATIVE "The imagination... organizing (as it were) the flux of the senses... gives birth to a system of symbols. . . consubstantial with the truths of which they are the conductors.“ Coleridge, 1816

  37. FALSE CONFIDENCE "What a man believes upon grossly insufficient evidence is an index into his desires — desires of which he himself is often unconscious. If a man is offered a fact which goes against his instincts, he will scrutinize it closely, and unless the evidence is overwhelming, he will refuse to believe it. If, on the other hand, he is offered something which affords a reason for acting in accordance to his instincts, he will accept it even on the slightest evidence. The origin of myths is explained in this way.” --Bertrand Russell ...

  38. BUT IS MYTH SO BAD? “These things never were,” said Sallust, speaking of the Greek myths, “but always are!” “Is there anything truer than truth?” Asked Kazantzakis, “Yes, Legend.” Is there a “higher truth?” Truth and Reality

  39. Is IMAGINATION the crucible of TRUTH ? Abstraction / umwelt Archetypal Ideal The common features of countless experiences

  40. IMAGINATION? “Not only is the universe stranger than we imagine, it is stranger than we can imagine.” (Sir Arthur Eddington) There is no excellent beauty that hath not some strangeness in the proportion. (Bacon, Essays (1625) ‘Of Beauty’). Truth and Reality

  41. Can we handle the truth?

  42. Are beliefs more important than truth?TRUTH and STRESS SELF-DECEPTION serves a vital function(Daniel Goleman’s use of Ibsen’s term: “Vital Lies” 1985) “You can’t handle the truth!” (Jack Nicholson in In “A Few Good Men,” 1992) DENIAL ---The more-or-less “…willing suspension of disbelief…” (Wordsworth) – is that the function of art?… to provide a safe zone for exploring the otherwise troubling, stress-evoking truth? Or of myth? (“theory used to be an “enchanted circle”)

  43. DISORDERS of BELIEF? Acceptance of experience that doesn’t correspond to external reality:kinds of hallucinations; Bonnet’s Syndrome(filling in scotoma); dismorphic body; pareidolia. (False positive (confident match with memories); Type I Error; gullible, trusting) Denial of experience that corresponds to external reality: agnosias: eg, visual(left occip), associative, anasognosia(denial of dysfunction / right cerebral cortices), prosopagnosia(faces) (False negative (failure to match with memories); Type II Error; skeptical, wary)

  44. POWER of EXPECTATIONS PLACEBO: the power of coherence: • Acupuncture IS effective in many cases, but application at arbitrary sites is comparable (Melchart et al. 2005) • Antidepressant medications can be 80% replicated with placebo (Kirsch et al. 2002) • Parkinson’s patients experience an endogenous dopamine “rush” when nigrostriatal system activated by placebo (expectation of reward – Fuente-Fernandez 2001)

  45. PLACEBO EFFECTnot merely subjective? Extra endorphins were also released from sites not usually engaged in analgesia, including • rostral anterior cingulate (perception of degree of pain)(ACC: autonomic, error-detection, conflict resolution or management) • insular cortex (receives somatic pain information) • nucleus accumbens (assesses urgency of pain) • dorsolateral prefrontal cortex(involved in decision making, interpretation, and selective attention) BUT, only in those that expected relief. (Zubieta et al. 2005) . . .

  46. gnosis • ANOSOGNOSIA -- Disorder of “insight” … denial of obvious condition (from the Greek: A + nosos (disease) + gnosis (knowledge) • HYPERGNOSIA -- Disorder of knowing; possessing an overwhelming indubitable conviction. (limbic epilepsy)

  47. Anosognosia • ANOSOGNOSIA(from the Greek: A + nosos (disease) + gnosis (knowledge) • Ignorance or denial of the presence of disease • Most famously of paralysis in patients with non-dominant (usually right) parietal lobe damage -- patients deny their hemiparesis, & confabulate rationalizations • Detection of discrepencies impaired • When the right hemisphere is denied input from the reality-testing of the left hemisphere; internal model is “untested” by feedback, leaving left-side function seemingly “hallucinated.”

  48. Putative Causes of Anosognosia • Freudian denial: avoidance of confrontation with dysfunction, preserve self image. • Phantom function: as with phantom limbs, signals from motor cortex go to parietal monitoring area AND to muscles (that no longer exist). In the absence of feedback (confirming dysfunction) parietal area prevails • Right hemisphere impairmentby muting emotionality, and flattening affect, might create the appearance of indifference

  49. Coherence and Confabulation • “The production of coherent but fictitious stories” • First observed by Korsakoff in alcoholics • Can be provoked (eg., to avoid embarassment) or spontaneous (Schnider 2003) • Involve anterior limbic structures (orbitofrontal) • Impressive when right hemisphere (and its “reality-check” on the left hemisphere) is damaged

  50. Coherence and Confabulation • Right hemisphere stroke: denial of left side paralysis. • Korsakoff’s syndrome: inability to form new memories due to temporal lobe dysfunction. • Acting out after a hypnotic suggestion will be rationalized with improvised confabulations • Schizophrenia: confabulations to rationalize hallucinations or to justify paranoia • Capgras syndrome: incomplete sense of who owns a familiar face: alien imposters?

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