Presentation on theme: "Phil 3318: Philosophy of Science Categorization & the influence of Auxiliary hypotheses."— Presentation transcript:
Phil 3318: Philosophy of Science Categorization & the influence of Auxiliary hypotheses
Induction v Deduction Not Truth Preserving Ampliative Spectral (reasoning with probability) Truth Preserving Non-ampliative All or nothing (reasoning with necessity)
Ampliative I saw a white swan Therefore, all swans are white All swans are white. Therefore, the swan that I saw was white.
Probability We have 10 male and 10 female freshman in this class. Therefore, 50% of all freshmen are male 50% of all freshman are male Therefore, a freshman chosen at random has a 50% chance of being male.
Simplistic inductivist account of science. Quote on pg. 11 of Hempel 1.Observe and record all facts. 2.Analyze and classify these facts. 3.Derive generalizations about them inductively. 4.Further test those generalizations.
Problems Problems: 1.It would never get started 2.Auxiliary hypotheses influence categorization and observation. 3.There are no ‘formal’ or ‘mechanical’ rules for generating inductive hypotheses.
The DN Model of Explanation Explanations are sound arguments (valid w/ true premises) that entail the event to be explained. L 1, L 2, … L n F 1, F 2, … F n E Explanans Explanandum Laws (usually conditionals) Facts Phenomenon Explained
Example Explanations are sound arguments (valid w/ true premises) that entail the event to be explained. For all cases, if you stimulate the L cone, the subject experiences a sensation of red. My L cone is stimulated Therefore, I have a sensation of red. Explanans Explanandum
H-D Notice the relation to the H-D method: For all cases, if you stimulate the L cone, the subject will experience a sensation of red. I am not experience red Therefore, my cone is not stimulated Explanans Explanandum Notice also that all explanandi are potential predictions!
When predictions fail: Auxiliary hypotheses are at fault! For all cases, if you stimulate the L cone and the M cone, the subject will experience a sensation of reddish-green. My L and M cones are stimulated Therefore, I am experiencing reddish- green Explanans Explanandum
When predictions fail: For all cases, if you stimulate the L cone and the M cone and the psychological character of sensations tells us (with certainty) what color is to be explained, then the subject will experience a sensation of reddish-green My L and M cones are stimulated Therefore, I am experiencing reddish- green Explanans Explanandum
Hermann von Helmholtz (1821-1894) Short = Purple Middle = GreenLong = Red
Historical Note: In 1877, Ladd-Franklin became the first woman to attend (albeit unofficially) Johns Hopkins where she studied mathematics. She wrote a dissertation under the supervision of C.S. Pierce. It was published in 1883, but her Ph.D. was not awarded until 1926! Even though she had studied under Helmholtz and had published a great deal in psychological journals, she was never admitted to the American Psychological Association meetings to present her papers. While she lectured at John Hopkins, Columbia, Clark, Harvard and Chicago, she never held an official academic post, and she was rarely paid. Her book Color and Color Theories was finally published in 1929, one year before her death.
Ladd-Franklin (1847-1930) IF stimulating the long-wavelength cone yields a red experience, and stimulating the middle-wavelength cone yields a green experience, THEN stimulating both the long and middle- wavelength cone would…. yield an experience of reddish-green
L-F’s argument (≈1892) IF stimulating the long-wavelength cone yields a red experience, and stimulating the middle-wavelength cone yields a green experience, THEN stimulating both the long and middle- wavelength cone would yield an experience of reddish-green Stimulating L and M yields an experience of yellow. THEREFORE, Helmholtz’s theory is NOT true Yellow does NOT look like reddish-green. THEREFORE, yellow is NOT reddish-green. Good Argument Right?
Why not? “Helmholtz deemed it illegitimate or at least untrustworthy to draw conclusions as to physiological processes from the direct psychological character of the sensations” -Von Kries
Helmholtz’s response IF stimulating the Long-wavelength cone yeilds a red experience, and stimulating the middle-wavelength cone yields a green experience, THEN stimulating both the Long and Middle- wavelength cone would yield an experience of reddish-green Stimulating L and M yields an experience of yellow. THEREFORE, Helmholtz’s theory is NOT true THEREFORE, Yellow is NOT reddish-green. Yellow does NOT look like reddish-green. BUT: One cannot draw conclusions about the physiology of color from this fact, so it does not follow that: yellow is not reddish-green or greenish-red.
Note: The Gestalt Psychologist David Katz made the phenomenology of color appearance the starting point for a theory of color (1908).
Definitions of ‘Memory’ Maybe, my memory for IP addresses isn’t really ‘memory’? http://inquiry.wustl.edu/newFrames/modules.p hp?mod_id=437 For all normal humans, we only have the ability to remember 7 digits +/- 2 I’m a normal human Therefore, I can only remember 7 digits +/- 2
Philosophers: (Plato / Aristotle?), Bergson, Russell, Ryle all distinguish between knowing how and knowing that. This distinction is transposed into memory: –I remember how to do arithmetic. –I remember that 2+2=4. –I remember how to get to Sears –I remember that Sears is on the corner of …
Further Distinctions: I just remembered that I am supposed to be in class! Remember when Janet Jackson had her ‘wardrobe malfunction’? Remember where you were when the Towers collapsed? Pavlov’s dog. Priming
Motor Skills Memory LTMSTM Non-Declarative (Implicit) Declarative (Explicit) Episodic (Events) Semantic (Facts) PrimingClassical Conditioning 1. Splitting Dissociable Kinds of Memory 1. Splitting Dissociable Kinds of Memory
H.M. from the Perspective of Cognitive Neuropsychology Develop Taxonomies of Memory Characterize Different Types of Memory Understand Neuro- cognitive Mechanisms Memory LTMSTM Non-Declarative (Implicit) Declarative (Explicit) Episodic (Events) Semantic (Facts) PrimingClassical Conditioning Motor Skills
The Hippocampus Identify set of tasks on which H.M. succeeds (T S ). Identify set of tasks on which he fails (T F ). Conjecture some cognitive faculty required for each task in T S and for no task in T F.
On which tasks does H.M. succeed? Perceptual and motor. I.Q. tests. Mirror Drawing. Gollins Partial Pictures. Priming. Classical and Operant Conditioning. Language.
On which tasks does H.M. fail? Conscious recognition of facts and events (Squire) Regardless of kind of test (free recall, cued recall, recognition) Regardless of material (e.g., words, digits, faces, mazes, life events) Regardless of sensory modality Conclusion: Loss of “Declarative Memory”
Dissociation and the Taxonomy of Memory A major theme in current studies of both humans and experimental animals is that memory is not a single entity but is composed of separate systems (Weiskrantz, 1990; Squire, 1992; Schacter and Tulving, 1994). The dissociation between declarative (explicit) and nondeclarative (implicit) memory is based on studies of experimental animals as well as amnesic patients and normal subjects showing that fact-and-event memory is distinct from other kinds of memory (skills, habits, and priming). –Squire and Knowlton
Memory Dissociation Argument in Philosophy Some X is a ‘natural kind’ iff in no possible world do parts of X exist without the whole and X still exists in that world (I.e. H2 w/out the O is not water). Hume’s claim: Two events are causally connected if and only if one might occur without the other. Why? –Because nothing can cause itself. –And if two events are necessarily conjoined, they are the same event (with the exception of two events that are both caused by a third event like ‘Socrates dying’ and ‘Xantippe becoming a widow’).
Memory Dissociation Argument in Neuroscience 1.Declarative memory and procedural memory can be independently disrupted. 2.Mechanistic Splitting: If two kinds can be independently disrupted, then they are explained by two distinct mechanisms. 3.Procedural and Declarative Memory have distinct mechanisms. 4.No Dissociable Mechanisms. Natural kinds are explained by one kind of mechanism. If there are two distinct mechanisms for a putative instance of a kind, there are really two kinds, one for each mechanism. 5.So Procedural and Declarative Memory are distinct natural kinds.