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Overview of Talk The Problem of Theory Ladenness II. Ecological Validity Argument

Naturalized Approaches to Theory Ladenness: Evidence from Cognitive Psychology, History, and the Ecological Validity Argument William F. Brewer University of Illinois at Urbana-Champaign

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Overview of Talk The Problem of Theory Ladenness II. Ecological Validity Argument

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  1. Naturalized Approaches to Theory Ladenness: Evidence from Cognitive Psychology, History, and the Ecological Validity Argument William F. Brewer University of Illinois at Urbana-Champaign Talk Presented at the Conference on the Theory-Ladenness of Experience, Heinrich-Heine University, Düsseldorf, Germany, March 10-11, 2011

  2. Overview of Talk • The Problem of Theory Ladenness II. Ecological Validity Argument A. A Conceptual argument III.Naturalized Phil of Sci • A. Framework from Cog Psy • B. Data from Cog Psy • C. Evidence from History of Sci • D. Conclusion

  3. The Problem--Theory Ladenness A. Norwood Hanson 1. Tycho Brahe/Kepler thought experiment 2. “seeing is a ‘theory-laden’ undertaking” (1958, p. 19) 3. “we usually see through spectacles made of our past experience [and] our knowledge” (1969, p. 149). B. Thomas Kuhn 1. "Lavoisier...saw oxygen where Priestly had seen dephlogisticated air and where others had seen nothing at all” (Kuhn, 1962, p. 117).

  4. 2. "After a revolution scientists are responding to a different world" (Kuhn, 1962, p. 110). C. Very strong psychological claims 1. clear case in Phil of Sci of need for a naturalized approach D Led some folk to relativism 1. Thus the epistemological message of [this] work could be said to be..relativistic...It is relativistic because it suggests that belief systems cannot be objectively ranked in terms of their proximity to reality or their rationality." (Barnes, 1974, pp. 154)

  5. E. Fodor counterattacks with modularity (1983, 1984) 1. early perceptual processing occurs in modules that are not cognitively penetrable by the higher order cognition required by the theory laden claims 2. ‘objectivity’ of science saved! F. Supported by: 1. Raftopoulos (2001a, 2001b) 2. Gilman (1990, 1992)

  6. The Ecological Validity Argument A. Neisser (1978) “Memory: What are the important questions?” 1. many laboratory memory tasks not relevant to phenomena of memory in real world B. Brewer (2001) Ecological Validity in Psy Research 1. there needs to be a clear link between the laboratory tasks studied by the scientist and the phenomena in the world the scientist is trying to understand 2. example: nonsense syllable learning literature in experimental psychology did not seem to be relevant to understanding memory for syntax, word meaning, schemata, etc.

  7. C. Ecological Validity as Applied to Theory Ladenness 1. the naturalistic data of interest to us are data relevant to the tasks the scientist carries out 2. we are interested in knowing if theory ladenness occurs for the the scientist’s perceptions of the objects the scientist is studying 3. we are interested in knowing if theory ladenness occurs for the scientist’s attention to the objects the scientist is studying D. The Data Discussed by the Modularity Mafia do Not Have the Required Ecological Validity 1. Fodor (1983, 1984) & Raftopoulos (2001a, 2001b) give us interesting data from studies of the very earliest stages of visual and neural processing

  8. 2. while the issues of the timing of the processing path for vision are of interest to vision scientists they are not the data we need in the Phil of Sci to address the theory ladenness issue 3. for the problems of interest to us we simply do not need to know if there is an early stage in vision (e.g., Marr’s 2 1/2 D) that is not cognitively penetrable. 4. for the issues of the Phil of Sci we need to know the outcome of the processing 5. to resolve the issues related to theory ladenness we need to know what the scientist perceived and what the scientist attended to in carrying out the process of science

  9. E. Apply the Ecological Validity Criterion to the Lab Data from Cog Psy in this Talk 1. I also have to play by these tough rules 2. You should compare the laboratory data I review to the episodes from the history of science and decide for yourself if the laboratory findings seem directed at the issues of interest (i.e. are ecologically valid) F. So What do the Relevant Naturalized Data Tell Us? 1. I claim the ecological argument undercuts the data that the modularity approach has attempted to use to eliminate the epistemological problems raised by theory ladenness 2. The core of this talk is a review of the appropriate evidence from current Cog Psy on the issue of theory ladenness.

  10. A Framework for Understanding Theory Ladenness A. Overemphasis of the Role of Visual Perception 1. There is a long history in Western philosophy of focusing on visual perception in epistemology 2. British Empiricists a. Hume, Berkeley, Lock 3. Logical Positivists 4. Kuhn & Hanson postPositivists 5. Fodor’s modularity approach

  11. B. Problems with this Overemphasis 1. “It is data rather than perceptual beliefs that play a central evidential role in science and data are typically not descriptions of perceptual appearances or reports of perceptual belief at all" (Bogen & Woodward, 1992 p, 599). 2. in modern science with computer-based data acquisition and analysis the actual data used is rarely the direct perceptual observations of the individual scientist

  12. C. Brewer & Lambert 2001 1. In Psychology of Science we want to study the scientific process from the initial designing of experiments to the final writing of a journal article 2. this approach reduces the role of visual perception but expands the potential role of top down influences to cover a much wider range 3. potentially relevant mental processes: a. perception b. attention c. thinking d. experimenting e. memory f. communication of findings

  13. D. Term “Theory will be Used Broadly 1. in this talk will ignore the literature on different forms of mental representation (images, concepts, schemas, mental models, etc) 2. in this talk theory = any form of top-down knowledge E. Laboratory Data Derived from Nonscientist Participants 1. in an ideal world the data from Cog Psy would be based on studies of actual scientists 2. in practice almost all of the data will be from children and undergraduate participants (actual data from scientists will be discussed along with the historical cases)

  14. 3. while there are many differences between scientists and ordinary folk we hope that the underlying mental processes are the same F. Top Down--Bottom Up Synthesis 1. modern framework (e.g., Lindsay & Norman, 1977) a. perception is conceived as the product of both bottom-up and top-down factors b. bottom-up: physical information coming into the eye or other sensory organ c. top-down: beliefs or theories about what the individual is perceiving 2. connectionist approaches (e.g., McClelland & Rumelhart, 1981) a. give a natural account of the interaction of the two forms of information

  15. 3. neuroscience a. recent work suggests there are actually more top-down descending neural pathways than ascending paths in the visual system 4. epistemological consequences a. allows evidence for top-down theory-driven effects b. bottom-up information from the world can help avoid the slippery slope to relativism 5. Fodor’s modularity view a. rejects the top/down-bottom-up view which is the modal view in current cognitive psychology b. given Fodor’s visibility in philosophy I think it might be easy for philosophers not to realize that his view is not the standard view

  16. G. Strongest Top-down Effects Occur with Degraded Input 1. Brewer & Lambert, (1993, 2001); Brewer & Loschky, (2005) review of the Cog Psy literature suggests that the amount of information that comes from top-down processes various across perceptual tasks a. hallucinations & dreams = ~100% top-down a. vivid, unexpected object being attended to would involve much bottom up information 2. the examples where theory has a very strong effect on perception tend to be cases of degraded stimuli, stimuli being presented for a very short time, or ambiguous stimuli.

  17. H. Facilitatory & Inhibitory Role of Theory on Understanding the World (the Two Edged Sword) 1. Brewer & Lambert, (1993, 2001) focused too strongly on the negative role of top-down processes 2. we wanted to show the effects of the top-down processes and so emphasized laboratory studies and historical cases that typically showed a negative impact on the performance of the participant in the lab or the scientist in the historical episode 3. in laboratory studies we typically know what the stimuli was so we can easily determine if the impact of theory was facilitatory or inhibitory

  18. 4. the data show that having a correct theory about the stimulus can reduce perceptual thresholds, direct attention, etc. 5. (old fashioned view about to come!) I want to argue in this talk that the historical episodes from the history of science can be treated the same way. In science we often know which view of the world was correct (no scare quotes!). So practicing Whig History in the history of science allows us to better understand the psychological processes that were occurring at the time (of course, the scientist working in real time never knows if the theory they are working with maps the world successfully)

  19. 6. so I claim that the scientist who is lucky enough to have a theory that reflects the nature of the world (most of us working scientists are un-reconstructed realists) will show the positive benefits of improved perception of the objects in the scientific domain, will be able to direct attention to the appropriate objects, will better be able to interpret information, etc. 7. and for the scientist who is unlucky enough to hold an incorrect view of the world there will be inhibition in all the same psychological processes in this scientist’s attempt to understand the world 8. this revived Whig History allows me to understand the psychological processes the were at work in many historical episodes

  20. 9. the Neptune/Vulcan example-- (a) when Galle received the theoretical information from Le Verrier about the likely location of Neptune it directed his attention to the correct region of the sky and allowed him to discover Neptune--a clear case of facilitation (b) however, when similar theoretical calculation were done for Mercury they led to many false sightings of the hypothetical planet Vulcan (a planet we now know does not exist)--a clear case of inhibition 10. so this (almost counterbalanced design!) supports my argument that when a scientist has a theory that correctly maps the world the mental processes will facilitate the ability of the scientist to understand the world, while the reverse in true for scientists with a theory that does not map the world

  21. I. Strategy in the Next Part of the Talk 1. take a naturalized approach to the philosophical discussions of the theory-ladenness of perception 2. study perception & the other processes 3. for each mental process--look for evidence from: a. cognitive psychology b. history of science

  22. Evidence on the Issue of Theory Ladennes from Cog Psy and History of Sci I. Perception--Psychological Evidence A. Overview --> 1. perception 2. attention 3. thinking 4. experimenting 5. memory 6. communication

  23. A. What do you see here?

  24. B. What do you see here?

  25. C. What do you see here?

  26. D. What do you see here?

  27. E. What do you see here?

  28. F. What do you see here?

  29. G. Ambiguous Figures--Perceptual Info (e.g., Leeper, 1935) 1. stimuli & procedure a. unambiguous version of an ambiguous figure b. note that this ambiguous figure gives rise to two different perceptual experiences c. later show ambiguous version d. ask what the participants see 2. results a. if 1st see unambiguous old woman then almost all participants see the ambiguous figure also as old woman b. if 1st see unambiguous young woman then almost all participants see the ambiguous figure as young woman 3. analogue in science: a. scientist looking at an idealized textbook drawing & then showing facilitation when looking a real slides 4. Bill Bechtel anecdote--anti interpretation

  30. H. Ambiguous Figures--Rat/Man (Bugelski & Alampay, 1961)

  31. I. Ambiguous Figures--Perc Class Info (e.g., Bugelski & Alampay, 1961) 1. stimuli & procedure a. show participants set of animal pictures (no rat) b. later show ambiguous rat/man picture c. ask what the participants see 2. results a. up to 80% of participants saw rat if had previously seen the set of animal pictures (

  32. J. Ambiguous Figures--Conceptual Info (e.g., Liu, 1976) 1. stimuli & procedure a. participants hear passage about rats b. later show ambiguous rat/man picture c. ask what the participants see 2. results a. doubled the rate of seeing the ambiguous figure as as rat 3. conclusion a. seems like a clear example of high-level conceptual theory information influencing the perceptual experience

  33. K. Vague Stimuli--Reynolds, 1985 1. stimuli: fragmented pictures a. initially seem to be random shapes (bottom-up info) then shift to being perceived as a meaningful obj 2. design: 3 conditions a. no info [9%] b. group told figs were meaningful picts [55%] c. group given more specific top down conceptual info (e.g. “animal”) [74%] 3. these stimuli give a Gestalt like experience (the random fragments are suddenly perceived as a meaningful object) so likely to be a true perceptual effect not a conceptual inference

  34. L. Reynolds 1985

  35. M. Vague Scientific Stimuli (Chinn & Malhotra, 2002) 1. it might be possible to use the ecological validity argument against the previous laboratory experiments 2. is there any theory laden evidence for an experimental situation even more like those in science? 3. children watching an actual scientific experiment 4. procedure a. experimenters show 4th grade children Galileo’s experiment of dropping heavy & light objects b. children must report if they saw: (1) heavy & light rocks hit at same time (2) heavy hit first or light hit first c. this a very difficult perceptual judgment

  36. 5. children have different naive theories: a. some believe heavy objects fall faster b. some believe both fall at same speed 4. results a. theory hit same 72% report both hit at same time b. heavy faster 25% report both hit at same time 5. this experiment does not provide ironclad evidence that the children’s theories influenced their perceptions, but they certainly show that the children’s theories influenced their observations and that is the crucial issues (for the ecological argument)

  37. N. Conclusions: Perception--Psychological Evidence 1. the experiments appear to give strong support to the top-down bottom-up synthesis. 2. note--in all the strong cases of theory ladenness the stimuli are ambiguous, degraded, or required a difficult perceptual judgment (so top-down factors can override the bottom up factors) 3. but strong bottom-up information will override top-down beliefs a. show Galileo a nice Voyager color photograph of Saturn and he would clearly see the rings

  38. 4. so no need to slide down the slippery slope to relativism 5. now shift to evidence from the history of science to see if it is consistent with the laboratory studies from psychology 6. the data from history cannot be, by its nature, as clear as the experiments where we can control and manipulate variables, but it also provides convincing evidence for the interplay of top-down and bottom-up processes in the perception of actual episodes in the history of science

  39. II. Perception--History of Science A. Overview --> 1. perception 2. attention 3. thinking 4. experimenting 5. memory 6. communication

  40. A. Rings of Saturn 1. astronomers were expecting to see moons circling Saturn since that is what they had seen with Jupiter 2. for 40 yrs they drew Saturn with a. moons or b. handles coming out of the poles 3. see drawings

  41. 4. Drawings of Saturn (Van Helden, 1974)

  42. B. Astronomer’s Psychological Conclusions 1. several astronomers have reviewed this and other examples of top-down factors in observational astronomy and have come to conclusions very similar to mine: 2. Sheehan (1988) stated “Once a definite expectation is established, it is inevitable that one will see something of what one expects; this reinforces and refines one’s expectations in a continuing process until finally one is seeing an exact and detailed--but ultimately fictitious--picture” (p. 85). 3. Sheehan also noted the role of theory in facilitating astronomical observation. He stated, “It is often wondered, after an object is once discovered, that it was not found long before. Faint objects are often reported as detectable in telescopes two or even three times smaller

  43. than those used for their discovery. Following the discovery of Saturn’s inner ring (the crépe ring)...for instance, the new ring was seen by a number of observers with small instruments” (p. 63). 4. Hetherington (1983) drew similar conclusions from the history of astronomy and concluded that having a theory is a two-edged sword. He pointed out that “scientists are guided by theory in selecting those observations that may be important” (p. 729) and that “the warping of judgments by knowledge, the influence on observational reports of preconceived opinion, is inevitable” (p. 729).

  44. C. N-rays 1. after discovery of X-rays physicists went looking for other new forms of radiation 2. 1903 famous French physicist, Blondlot, announced discovery of N-rays 3. N-rays (see slide) a. produced by Nernst lamp b. blocked by wet cardboard c. refracted by aluminum prism d. detection--a hard perceptual task (1) increase in spark gap or (2) by faint phosphorescent glow of paint in dark 4. 300 papers on properties of n-rays were published by 100 different scientists [ouch!] [one said discovered first!]

  45. 5. N-ray Apparatus

  46. 6. Wood, sceptical American physicist, went to Blondlot’s lab--in dark removed aluminum prism--experimenters could still see the n-rays--so by manipulating the physical factors while leaving the psychological ones constant he showed the effect was essentially all due to top-down theory 7. Conclusion (a) scientists with strong theoretical beliefs who have to make very difficult perceptual judgments show strong theory-laden perception

  47. D. Conclusions: Perception--Historical Evidence 1. the historical record also appear to give strong support to the top-down bottom-up synthesis. 2. when a scientist’s theories map the world the psychological processes facilitate understanding the world, but when the scientist’s theory does not map the world the psychological processes inhibit the scientist’s ability to understand the world 3. there are clear examples of theory ladenness, but as with the evidence from cognitive psychology experiments the top-down effects almost always occur when the stimuli are ambiguous, degraded, or required a difficult perceptual judgment

  48. 4. but strong bottom-up information will override the top-down beliefs: a. Tycho Brahe seeing a new star (supernova) b. if the data in Blondlot’s experiment had been observations of a 10 on a meter with a 1 to 10 scale it is likely that the N-ray affair would not have occurred) 5. so, once again, we are not driven to relativism (but instead to the need for controls against the possibility of top-down theory-laden processes influencing experiments)

  49. III. Attention--Psychological Evidence A. Overview 1. perception --> 2. attention 3. thinking 4. experimenting 5. memory 6. communication

  50. A. Laboratory Inattentional Blindness (Mack & Rock, 1998) 1. stimuli--cross presented very rapidly (200ms) faster than a shift in eye fixation possible 2. participants asked which arm of cross was longer 3. on a critical trial a totally unexpected objects (e.g., a small black square) was presented within one of the quadrants of the cross 4. depending on details of the experimental procedures from 25% to 80% report not having seen the unexpected object 5. control procedure of not asking for cross judgments and asking participants to report anything they saw showed essentially 100% reports of the unexpected object

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