Citation Context

...ty. With respect to possible sources of conviction in TEs beyond (a) and (b) above, other evidence indicates that schema-driven simulations can work in concert with more general spatial reasoning skills. These general skills are reasoning operations J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 695 that reflect spatio-temporal constraints on any system of objects, such as the constraint that solid objects may not occupy the same space, or that two sequential displacements of the same object will add together, or that the face of an object turning on an axis will disappear and reappear (Shepard & Cooper, 1982). Elementary spatial reasoning operations are processed automatically without noticeable effort. One can add to the list of possible subprocesses in an imagistic simulation: (c) Spatial reasoning can contribute inferences, such as were apparently needed in Episode 2 where the bending going on in successive sections of the spring is imagined to add together and produce an increasing slope in the wire. A similar process is hypothesized to occur in Episodes 4 and 5 when the subject imagines whether the contributions to stretching and slope in each side of the square coil accumulate. (He predicts ...

Citation Context

..., 2008). In this paper I have focused only on mechanisms for running and drawing conclusions from TEs. More work is needed to evaluate, augment, and refine our understanding of these mechanisms as well as generation mechanisms. 8.2. Flexibility Interest has increased in the role perceptual processing plays in grounding the meaning of cognitive representations (e.g., Barsalou, 1999); one can also ask related questions such as: Is there any role for thinking at a perceptual motor level that connects it in an important way with creative scientific reasoning and theory formation at higher levels? Piaget (1955) emphasized that the natural extendibility and flexibility of perceptual motor schemas are extremely valuable properties, allowing them to be used in new circumstances. It can be argued that each of the four sources of new knowledge and conviction described earlier exemplifies how the natural flexibility of perceptual motor schemas can be utilized to advantage during scientific thinking through imagistic simulation. For example, in the square coil in Episodes 4 and 5, one sees how the flexible perceptual motor schemas for bending and twisting can be combined and run in a new context in order t...

Citation Context

...rposes and mechanisms for TEs as they are being used for the first time by a reasoner. 2. Purpose and method In this paper I will analyze examples of qualitative thought experiment episodes from think-aloud case studies in an attempt to provide some evidence of this kind. Unfortunately, there is not even a consensus in the literature on a definition for ‘‘thought experiment.’’ The goal of this study is to provide some initial documentation of the use of spontaneous TEs and to use these to suggest a modeling framework for a mechanism that can begin to address the paradox. In doing so, I follow Anzai and Simon (1979) in considering think-aloud case studies to be an important strategy for constraining initial modeling in an underdeveloped area. Partly because the TEs discussed here appear to involve dynamic imagery and internal simulations, I do not intend to develop a computational model, but to concentrate on the prior task of trying to sort out a consistent way to describe relationships between concepts like ‘‘simulation,’’ ‘‘perceptual motor schema,’’ ‘‘imagery,’’ and ‘‘mental model’’ during the running of a thought experiment. To do this I will focus most on a single expert subject in an attempt to ac...

Citation Context

...fruitfully with both educational applications and the analysis of historical TEs. J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 707 Notes 1. There is not space here, but Clement (2008) discusses more than a dozen other indicators associated with imagery and reviews an increasing variety of studies of depictive gestures that suggest they are concurrent expressions of core meanings or reasoning strategies and not simply delayed translations of speech. Other studies indicate that the same brain areas are active during real actions and corresponding imagined actions (Decety & Ingvar, 1990; Roland, Larsen, Lassen, & Skinhoj, 1980). This suggests that depictive gestures are natural, abbreviated outputs reflecting internal imagery. 2. With regard to the relationship between schemas, implicit knowledge, and mental models, by considering the example of using a twisting schema to examine whether longer objects are easier to twist than shorter ones, one can ask whether ‘‘twisting the image of a rod’’ should be considered the use of a mental model. If no, then some TEs can be performed without models. If yes, then one is stretching the use of the term ‘‘model’’ to include the action of a basic perceptual motor schema on an i...

Citation Context

...ount, should be irrelevant to inferencing. In comparison, the imagistic simulation framework developed so far appears to offer a more viable way to explain ‘‘imagery enhancement’’ episodes. And the subjects’ efforts to produce them also argues that they valued imagery-based methods as important. 5.1. Imagery enhancement in a historical TE Enhancement may also have played a role in historical TEs such as those Einstein created for general relativity. His goal was to show ‘‘how the problem of the general relativity theory (for accelerated motion) is closely connected with that of gravitation’’ (Einstein & Infeld, 1938, p. 222). He describes his first version of a TE in this area coming to him in the patent office as the case of a person falling (e.g., from a tall building). He concluded, ‘‘If a person falls freely he will not feel his own weight.’’ That this was an important insight for him is supported by his referring to it as ‘‘the happiest thought in my life’’ (letter by Einstein quoted in Isaacson, 2007, p. 145). He subsequently enhanced the experiment by J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 699 placing the person in a closed, windowless container such as an elevator. He invites us to ...

Citation Context

...ns are infallible indicators on their own but are used here as evidence for imagery, and this is reinforced when more than one appear together. All indicators above except object or location gestures or reports of static imagery are also evidence for dynamic imagery of the kind that could be used in a simulation. Such indicators appear alongside new thought experiment predictions in the protocol segments, supporting the hypothesis that some type of internal imagistic simulation is occurring. 4.2.2. Schema-driven simulations One can also draw on the historical precedent of motor schema theory (Schmidt, 1982) in hypothesizing that analog perceptual motor knowledge structures that can control real actions over time (e.g., a schema for ‘‘twisting’’ objects) are involved here. The observations in Episode 7, for example, can be explained via what I have called a schema-driven imagistic simulation, as follows: (a) The subject has activated a somewhat general and permanent perceptual motor schema that can control the action of twisting real objects; the schema is capable of coordinating real actions and perceptions over time and does this partly by generating action command trajectories and perceptual e...

Citation Context

...gined experience than the articulation of an argument. It differs from rule-based argument by utilizing creative, extended applications of schemas, involving applicability judgments; emergent properties from compound simulations; and spatial reasoning, which in elementary cases is applied ‘‘automatically’’ rather than in an explicit argument. The process in the dotted box in Fig. 5, faced with an unfamiliar context, is more like one or more motor schemas extending creatively to engage in an exploratory action than it is a rule-based argument. This view is consistent with other authors such as Hegarty (2004) who distinguish between analog reasoning via mental simulation and rule-based reasoning. For precedents on the rationalist side, the use of (c), spatial reasoning processes, is the source in Fig. 5 that comes closest to Brown’s (2004) hypothesized Platonic ‘‘intuitions of the laws of nature’’ since spatial reasoning may be so deeply embedded or embodied in the system. Shepard (2008) hypothesized that many of these spatial reasoning processes are innate, but specifying the extent to which some could be innate is a current developmental research issue. Nersessian (1992) provided evidence for th...

Citation Context

...-grained information in historical data, we lack empirical information on whether something like mental simulation is actually used, and if so what its components are and what the sources of knowledge are within it. J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 687 My own interest in this area began during a study of spontaneous analogies in think-aloud studies of expert reasoning in which we noticed that, in contrast to the usual view of an analogous case as already residing in memory, several of the cases were quite novel, indicating that they had been invented rather than retrieved (Clement, 1988). The papers described this finding from protocols as documenting the spontaneous generation of Gedanken experiments by experts, since that is a term often used in the history of physics for invented TEs. Subsequently, Clement (1994) analyzed data from expert protocols to propose mechanisms for what was termed the imagistic simulation process, with the goal of providing a foundation for understanding thought experiment processes. Eventually this was expanded into a larger theory of sources of knowledge in TEs (Clement, 2002, 2008). The present paper elaborates this theory on the basis of think...

Citation Context

...ope. The flexibility of a system that can produce compound simulations and that can be run in a representation that incorporates physical and spatial constraints through spatial reasoning pays off in being able to generate novel predictions from a new runnable model. Ippolito and Tweney (1995) discuss how abilities related to these may also guide the interactions of scientists with real experiments. 8.3. Imagistic simulation can ground higher levels of processing An extension of this theme is to suggest that imagistic simulations provide a foundation for more sophisticated types of reasoning. Clement (1989) discusses a subtype of mental model, explanatory models; these hypothesize a hidden theoretical mechanism operating within a system to explain the behavior of the system. In this paper I have cited protocol examples of TEs run via schema-driven imagistic simulations where the simulations are not only run directly on the target (Episode 1), but are run within an explanatory model for the target (Episode 2), within an analogy (Episodes 3, 4, 5, 9, cf. Clement, 2004), and within an evaluative Gedanken experiment (Episode 11). Thus, TEs using imagistic simulation may 706 J. J. Clement ⁄ Topics in...

Citation Context

...a scientific thought experiment. Scientists such as Galileo, Newton, Correspondence should be sent to John J. Clement, Scientific Reasoning Research Institute, Lederle 434, University of Massachusetts, Amherst, MA 01003. E-mail: clement@srri.umass.edu Topics in Cognitive Science 1 (2009) 686–710 Copyright 2009 Cognitive Science Society, Inc. All rights reserved. ISSN: 1756-8757 print / 1756-8765 online DOI: 10.1111/j.1756-8765.2009.01031.x Einstein, and Maxwell have included powerful thought experiments (TEs) in their published works. History of science investigations of TEs include that of Nersessian (2002) who has proposed, based on her reading of historical records of Maxwell’s work on electromagnetic field theory, that TEs can play a role in the development of scientific theories, not just in their exposition. Related processes that can be interpreted as utilizing TEs have been documented using the laboratory notes of Michael Faraday by Gooding (1992) and Ippolito and Tweney (1995). Thought experiments are intriguing because (a) they appear to play a powerful role in science; and (b) the subject seems to gain what feels like new empirical information without making any new observations. This ...

Citation Context

...can be a more complex reasoning pattern than the simple TEs discussed earlier. In this particular kind of Gedanken experiment, the subject considers a new system for which the present model is predictive but for which another source of knowledge is also predictive, giving the potential for conflict or coherence between the two prediction methods. (Other examples are given in Clement, 2008.) J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 701 6.1. Galileo’s cannonball through a hole in the Earth experiment A similar pattern can be seen in the beautiful experiment shown in Fig. 7B, used by Galileo (2001) in his Dialogues on the Two Chief World Systems. (Versions can also be traced back at least as far as his predecessor Tartaglia.) The larger issue at hand is whether Aristotle’s distinction of ‘‘Natural’’ and ‘‘Violent’’ motion as two different types of motion is valid. Here, ‘‘Natural’’ motion is motion toward the center of the Earth, whereas upward movement, such as throwing a ball up, is ‘‘Violent’’ (preternatural or ‘‘constrained’’) motion. Drilling a hole through the Earth and dropping a cannonball into it appears to produce, at the center of the Earth, a smooth but very sudden transitio...

Citation Context

...opics in Cognitive Science 1 (2009) 687 My own interest in this area began during a study of spontaneous analogies in think-aloud studies of expert reasoning in which we noticed that, in contrast to the usual view of an analogous case as already residing in memory, several of the cases were quite novel, indicating that they had been invented rather than retrieved (Clement, 1988). The papers described this finding from protocols as documenting the spontaneous generation of Gedanken experiments by experts, since that is a term often used in the history of physics for invented TEs. Subsequently, Clement (1994) analyzed data from expert protocols to propose mechanisms for what was termed the imagistic simulation process, with the goal of providing a foundation for understanding thought experiment processes. Eventually this was expanded into a larger theory of sources of knowledge in TEs (Clement, 2002, 2008). The present paper elaborates this theory on the basis of think-aloud case studies and places it in the context of other work on the problem of TEs. With respect to the question of purposes for TEs, Kuhn (1977) theorized that the role of TEs was to disclose a conflict between one’s existing conc...

Citation Context

...mas, implicit prior knowledge, and spatial reasoning operations, in contrast to formal arguments. These sources suggest what it means for TEs to be grounded in embodied processes that can begin to explain the paradox above. This leads to a rationalistic view of TEs as using productive internal reasoning, but the view also acknowledges the historical role that experience with the world can play in forming certain schemas used in TEs. Understanding such processes could help provide a foundation for developing a larger model of scientific investigation processes grounded on imagistic simulation (Clement, 2008). Keywords: Scientific thinking; Imagery; Mental simulation; Embodied cognition; Reasoning; Creativity 1. Introduction This article focuses on understanding what is happening when an expert makes new or novel predictions in a scientific thought experiment. Scientists such as Galileo, Newton, Correspondence should be sent to John J. Clement, Scientific Reasoning Research Institute, Lederle 434, University of Massachusetts, Amherst, MA 01003. E-mail: clement@srri.umass.edu Topics in Cognitive Science 1 (2009) 686–710 Copyright 2009 Cognitive Science Society, Inc. All rights reserved. ISSN: 175...

Citation Context

...those Einstein created for general relativity. His goal was to show ‘‘how the problem of the general relativity theory (for accelerated motion) is closely connected with that of gravitation’’ (Einstein & Infeld, 1938, p. 222). He describes his first version of a TE in this area coming to him in the patent office as the case of a person falling (e.g., from a tall building). He concluded, ‘‘If a person falls freely he will not feel his own weight.’’ That this was an important insight for him is supported by his referring to it as ‘‘the happiest thought in my life’’ (letter by Einstein quoted in Isaacson, 2007, p. 145). He subsequently enhanced the experiment by J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 699 placing the person in a closed, windowless container such as an elevator. He invites us to imagine that we could not tell the difference between being in an elevator floating in space and one in free fall dropping toward the earth. Nor could we distinguish between an elevator accelerating ‘‘upward’’ in outer space and one at rest in a gravitational field, since objects would appear to drop to the floor in the same way. This particular TE plays a generative rather than an evaluative ro...

Citation Context

...that this can interact fruitfully with both educational applications and the analysis of historical TEs. J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) 707 Notes 1. There is not space here, but Clement (2008) discusses more than a dozen other indicators associated with imagery and reviews an increasing variety of studies of depictive gestures that suggest they are concurrent expressions of core meanings or reasoning strategies and not simply delayed translations of speech. Other studies indicate that the same brain areas are active during real actions and corresponding imagined actions (Decety & Ingvar, 1990; Roland, Larsen, Lassen, & Skinhoj, 1980). This suggests that depictive gestures are natural, abbreviated outputs reflecting internal imagery. 2. With regard to the relationship between schemas, implicit knowledge, and mental models, by considering the example of using a twisting schema to examine whether longer objects are easier to twist than shorter ones, one can ask whether ‘‘twisting the image of a rod’’ should be considered the use of a mental model. If no, then some TEs can be performed without models. If yes, then one is stretching the use of the term ‘‘model’’ to include the action o...

Citation Context

...hat is a term often used in the history of physics for invented TEs. Subsequently, Clement (1994) analyzed data from expert protocols to propose mechanisms for what was termed the imagistic simulation process, with the goal of providing a foundation for understanding thought experiment processes. Eventually this was expanded into a larger theory of sources of knowledge in TEs (Clement, 2002, 2008). The present paper elaborates this theory on the basis of think-aloud case studies and places it in the context of other work on the problem of TEs. With respect to the question of purposes for TEs, Kuhn (1977) theorized that the role of TEs was to disclose a conflict between one’s existing concepts and nature. On the other hand, Brown (1991) identified several purposes that included constructive as well as destructive (conflict generating) TEs. He also theorized that a few special TEs could serve both functions. Nersessian’s (2002) analysis of Maxwell’s work hypothesized that a TE could expose conflicts in an existing theory but that it could also point to new constraints that help guide positive modifications of the theory, thus playing both a destructive and constructive role. Thus, a disparate v...

Citation Context

...o disconfirm Aristotle’s theory that heavy objects will fall faster than light objects. Galileo imagined a light object joined to a heavy object while falling, reasoning that under Aristotle’s assumptions the light object would slow the heavy object down; yet under those same assumptions, the total mass of the conjoined objects should fall faster than the heavy object alone, leading to a contradiction. Also on the rationalist side is Shepard (2008), who hypothesized that TEs may draw on imagined transformations depending on innate, presymbolic knowledge of threedimensional space and symmetry. Nersessian (1992) hypothesized that ‘‘simulative reasoning’’ using analog mental models played a role in Maxwell’s TEs on electromagnetic effects. Miscevic (2007) also focused on mental models, hypothesizing on theoretical grounds that the use of visualization could tap implicit spatial-geometric knowledge as a source. However, Gooding (1992), through his analysis of Faraday’s laboratory notebooks, emphasized the similarities between real experiments and TEs, arguing against a purely rationalist description. Although he recognizes the role of reasoning, he argues that TEs also involve distillations of pract...

Citation Context

...empts to deal with the fundamental paradox have ranged widely on a spectrum from empiricist to rationalist. For example, Norton (1996) claims that TEs are simply disguised arguments using the rules of inductive or deductive reasoning and that these start from tacit premises that can be suppressed empirical knowledge; he supports this position by displaying his own logical reconstructions of arguments he discerns in famous TEs. On the rationalist side, Gendler (1998) argues that the power of certain TEs used by scientists such as Galileo cannot be assigned to an underlying formal argument. And Brown (1991, 2004) believes that certain TEs utilize Platonistic apperceptions and nonformal reasoning to arrive at new conclusions that transcend experience, rather than starting from empirical propositions and extending them by formal arguments. (Unless qualified, in this paper I will use the term ‘‘reasoning’’ in a broad sense that can include nonformal heuristic reasoning that may not be rule based.) For example, he describes a method Galileo used to disconfirm Aristotle’s theory that heavy objects will fall faster than light objects. Galileo imagined a light object joined to a heavy object while fal...

Citation Context

...6-8757 print / 1756-8765 online DOI: 10.1111/j.1756-8765.2009.01031.x Einstein, and Maxwell have included powerful thought experiments (TEs) in their published works. History of science investigations of TEs include that of Nersessian (2002) who has proposed, based on her reading of historical records of Maxwell’s work on electromagnetic field theory, that TEs can play a role in the development of scientific theories, not just in their exposition. Related processes that can be interpreted as utilizing TEs have been documented using the laboratory notes of Michael Faraday by Gooding (1992) and Ippolito and Tweney (1995). Thought experiments are intriguing because (a) they appear to play a powerful role in science; and (b) the subject seems to gain what feels like new empirical information without making any new observations. This raises what I call the fundamental paradox of thought experiments, expressed as: ‘‘How can findings that carry conviction result from a new experiment conducted entirely within the head?’’ The idea of an experiment (involving observation) being conducted in the head (without observations) is paradoxical in that it seems self-contradictory. Interestingly, previous attempts to deal wi...

Citation Context

... observation) being conducted in the head (without observations) is paradoxical in that it seems self-contradictory. Interestingly, previous attempts to deal with the fundamental paradox have ranged widely on a spectrum from empiricist to rationalist. For example, Norton (1996) claims that TEs are simply disguised arguments using the rules of inductive or deductive reasoning and that these start from tacit premises that can be suppressed empirical knowledge; he supports this position by displaying his own logical reconstructions of arguments he discerns in famous TEs. On the rationalist side, Gendler (1998) argues that the power of certain TEs used by scientists such as Galileo cannot be assigned to an underlying formal argument. And Brown (1991, 2004) believes that certain TEs utilize Platonistic apperceptions and nonformal reasoning to arrive at new conclusions that transcend experience, rather than starting from empirical propositions and extending them by formal arguments. (Unless qualified, in this paper I will use the term ‘‘reasoning’’ in a broad sense that can include nonformal heuristic reasoning that may not be rule based.) For example, he describes a method Galileo used to disconfirm ...

Citation Context

...reserved. ISSN: 1756-8757 print / 1756-8765 online DOI: 10.1111/j.1756-8765.2009.01031.x Einstein, and Maxwell have included powerful thought experiments (TEs) in their published works. History of science investigations of TEs include that of Nersessian (2002) who has proposed, based on her reading of historical records of Maxwell’s work on electromagnetic field theory, that TEs can play a role in the development of scientific theories, not just in their exposition. Related processes that can be interpreted as utilizing TEs have been documented using the laboratory notes of Michael Faraday by Gooding (1992) and Ippolito and Tweney (1995). Thought experiments are intriguing because (a) they appear to play a powerful role in science; and (b) the subject seems to gain what feels like new empirical information without making any new observations. This raises what I call the fundamental paradox of thought experiments, expressed as: ‘‘How can findings that carry conviction result from a new experiment conducted entirely within the head?’’ The idea of an experiment (involving observation) being conducted in the head (without observations) is paradoxical in that it seems self-contradictory. Interestingl...

Citation Context

...simulations as the grounding level that influences three higher levels of processing during creative theory formation. These levels are, from next higher to highest: nonformal reasoning processes (including analogies and Gedanken experiments); cycles of generation and evaluation of runnable explanatory models; and higher-level investigation and application processes. 8.4. Implications A relatively small number of specific evaluative Gedanken experiments in the history of science have been recognized for their pedagogical value in convincing students of the validity or nonvalidity of a theory (Reiner & Gilbert, 2000). Occasionally, useful and interesting Gedanken experiments are generated by students themselves (Gilbert & Reiner, 2004). But with regard to untested TEs in the broad sense, in the present view, they are likely to be more ubiquitous in classrooms than previously thought because they appear within many types of reasoning (Stephens & Clement, in press). This suggests that they— along with imagistic simulation as a major mechanism—deserve additional study. 8.5. Summary Both the broad and specialized concepts of ‘‘thought experiment’’ proposed here appear to be useful, and both can be documented ...

Citation Context

... novel, indicating that they had been invented rather than retrieved (Clement, 1988). The papers described this finding from protocols as documenting the spontaneous generation of Gedanken experiments by experts, since that is a term often used in the history of physics for invented TEs. Subsequently, Clement (1994) analyzed data from expert protocols to propose mechanisms for what was termed the imagistic simulation process, with the goal of providing a foundation for understanding thought experiment processes. Eventually this was expanded into a larger theory of sources of knowledge in TEs (Clement, 2002, 2008). The present paper elaborates this theory on the basis of think-aloud case studies and places it in the context of other work on the problem of TEs. With respect to the question of purposes for TEs, Kuhn (1977) theorized that the role of TEs was to disclose a conflict between one’s existing concepts and nature. On the other hand, Brown (1991) identified several purposes that included constructive as well as destructive (conflict generating) TEs. He also theorized that a few special TEs could serve both functions. Nersessian’s (2002) analysis of Maxwell’s work hypothesized that a TE cou...

Citation Context

...n extension of this theme is to suggest that imagistic simulations provide a foundation for more sophisticated types of reasoning. Clement (1989) discusses a subtype of mental model, explanatory models; these hypothesize a hidden theoretical mechanism operating within a system to explain the behavior of the system. In this paper I have cited protocol examples of TEs run via schema-driven imagistic simulations where the simulations are not only run directly on the target (Episode 1), but are run within an explanatory model for the target (Episode 2), within an analogy (Episodes 3, 4, 5, 9, cf. Clement, 2004), and within an evaluative Gedanken experiment (Episode 11). Thus, TEs using imagistic simulation may 706 J. J. Clement ⁄ Topics in Cognitive Science 1 (2009) be an important mechanism operating within several types of nonformal reasoning. This theme and additional episodes of TEs conducted on more sophisticated qualitative and mathematical models of the spring are analyzed in Clement (2008); evidence is presented that argues for imagistic simulations as the grounding level that influences three higher levels of processing during creative theory formation. These levels are, from next higher to...

Citation Context

...ese levels are, from next higher to highest: nonformal reasoning processes (including analogies and Gedanken experiments); cycles of generation and evaluation of runnable explanatory models; and higher-level investigation and application processes. 8.4. Implications A relatively small number of specific evaluative Gedanken experiments in the history of science have been recognized for their pedagogical value in convincing students of the validity or nonvalidity of a theory (Reiner & Gilbert, 2000). Occasionally, useful and interesting Gedanken experiments are generated by students themselves (Gilbert & Reiner, 2004). But with regard to untested TEs in the broad sense, in the present view, they are likely to be more ubiquitous in classrooms than previously thought because they appear within many types of reasoning (Stephens & Clement, in press). This suggests that they— along with imagistic simulation as a major mechanism—deserve additional study. 8.5. Summary Both the broad and specialized concepts of ‘‘thought experiment’’ proposed here appear to be useful, and both can be documented in think-aloud protocols. The broad concept of an untested thought experiment is appropriate for expressing the fundament...

Citation Context

...(1977) ideas, Gooding (1992) observed that the successful TE author ‘‘selects and isolates just those features of a phenomenon, the environmental framework, and the conceptual scheme that are mutually problematic’’ (p. 71). Here it appears he is describing some general features of one design for what I have termed an evaluative Gedanken experiment. In doing so, he also took a position that is intermediate between the empiricist and rationalist ends of the spectrum, concluding with elegant simplicity, ‘‘What is needed is a combination of empirical knowledge and the ability to reason with it’’ (Gooding, 1994, p. 1041). Gedanken experiments are designed to help evaluate a theory, model, or concept. Examples like the band spring in Fig. 7 are more similar to real experiments in design and can include something like the control of variables, which may make them ‘‘feel’’ even more empirical. Galileo’s dropping balls experiment, discussed by Brown and mentioned in the introduction, has a similar Gedanken form to that of Fig. 7B except that the sources of conflict are both internal to the theory being attacked. The conclusions about nonformal mechanisms for untested TEs, reached in the discussion secti...

Citation Context

... term ‘‘reasoning’’ in a broad sense that can include nonformal heuristic reasoning that may not be rule based.) For example, he describes a method Galileo used to disconfirm Aristotle’s theory that heavy objects will fall faster than light objects. Galileo imagined a light object joined to a heavy object while falling, reasoning that under Aristotle’s assumptions the light object would slow the heavy object down; yet under those same assumptions, the total mass of the conjoined objects should fall faster than the heavy object alone, leading to a contradiction. Also on the rationalist side is Shepard (2008), who hypothesized that TEs may draw on imagined transformations depending on innate, presymbolic knowledge of threedimensional space and symmetry. Nersessian (1992) hypothesized that ‘‘simulative reasoning’’ using analog mental models played a role in Maxwell’s TEs on electromagnetic effects. Miscevic (2007) also focused on mental models, hypothesizing on theoretical grounds that the use of visualization could tap implicit spatial-geometric knowledge as a source. However, Gooding (1992), through his analysis of Faraday’s laboratory notebooks, emphasized the similarities between real experi...