Commonsense Reasoning about Processes: A Study of Ideas About Reversibility by Laercio Evandro Ferracioli da Silva A Thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in University of London Department of Science Education Institute of Education University of London February, 94 Abstract In recent years, research in students' conceptions about the physical world has revealed that when children reach the age of schooling they have already developed their own knowledge about the physical world which is sometimes rather different from the accepted scientific knowledge taught in schools. This thesis aims at investigating possible structures of commonsense reasoning about reversibility related to processes of interest to Science presented by students from two age-groups, 13/14 year old and 16/17 year old. The study has a theoretical framework based upon the scientific view of reversibility mainly related to Thermodynamics. It is also related to a conceptual, commonsense and developmental perspective taken from the literature, where reversibility is connected with different concepts such as causation, action, and conservation. Therefore, based upon this framework some very basic questions were asked to students about a selected number of phenomena. The empirical data was collected with the use of questionnaires. The sample consisted of two different age/instructional groups of students from England, Chile and Brazil. Factor Analysis was used to analyse the quantitative data. The qualitative data was analysed using a systemic network in which students' answers could be categorised. The main result of the quantitative analysis was a common three dimensional factor space of explanation for all groups with the dimensions relating to the ways in which the processes could be seen. They are respectively the contrast between 'can happen and cannot happen', 'needs an action and happens by itself, and 'has a goal and has no goal'. Phenomena can be located in this common space, but their position may vary for different age/instructional groups and for groups from different countries. The results of the qualitative analysis give a more detailed description of the way students see the reversibility of the processes and lend support to the quantitative results. 2 The concepts initially formed by abstraction from particular situations or experimental complexes acquire a life of their own. Werner Heisenberg 3 To my father, for his determination (in memorium), To my mother, for her perseverance, To my brother, for his passion for life, To my sister, for her love. 4 Acknowledgements I wish to express my gratitude to Professor Jon Michael Ogborn, the supervisor of this thesis, for his invaluable assistance and encouragement and personal help throughout the course of this work, which belongs to him as well. Should I also thank him for being able to learn from his experience from life and professionalism, and that 'life' is not a spontaneous process as it might seem to be. I am greatly indebted to Monica Pereira dos Santos, Compadre Wagner, Brother Edmundo and Carmen Gata for their friendship, support and encouragement as well as for their unconditional personal and emotional help, without which I could not have survived. I am also grateful to a group of friends for their help on different occasions, just to mention a few Isabel Martins, Maria José Benzanilla, Gwenn Edwards, Joel Castro, Clive Ellul, Gillian Nicholls, Fabio Sampaio. But I am grateful to all my colleagues at the research student group as well as the staff of the Science Education Department of the Institute of Education. My deepest gratitude is to the informants of this research and to school teachers and directors who helped me during the data collection, specially to D. Judith Pereira de Castro. Departamento de Fisica da Universidade Federal do Espirito Santo is gratefully acknowledged for granting me leave of absence to carry out this project. CNPq (Brazilian Research Council) is gratefully acknowledged for financial support. 5 Contents Abstract ii Acknowledgements Contents vi List of Figures xvi List of Tables xix 1 Introduction 1.1 The Context of the Research 21 1.2 The Organisation of the Thesis 23 2 Reversibility: A Scientific Perspective 2.1 System, Surrounding, Universe 25 2.2 Macroscopic Views of Mechanics and Thermodynamics 27 2.3 Thermodynamic Equilibrium 27 2.4 Process and Quasi-static Process 28 2.5 The First Law: Energy, Heat and Work 28 2.6 The Second Law: The Statement of Nature's Asymmetry 29 Contents - 7 2.7 Reversibility and Irreversibility 31 2.8 Spontaneity, Equilibrium, and Reversibility 32 2.9 Entropy 33 2.10 Entropy and 'Quality of Energy' 34 2.11 Entropy and the Direction of Time 34 2.12 Time-Reversible Processes 35 2.13 Entropy and Disorder: a Microscopic View of Thermodynamics 36 2.14 Order Out of Disorder 37 2.15 Time's Arrow 39 3 Review of Literature 3.1 Introduction 40 3.2 Studies in a Descriptive Perspective 42 3.2.1 Reversibility 43 3.2.2 Matter and its Transformations 44 3.2.2.1 Nature of Matter 44 3.2.2.2 State of Matter 46 3.2.2.3 Transformation of Matter 47 3.2.2.4 Chemical Changes 48 3.2.2.5 Physical Changes 50 3.2.2.6 Bio-Chemical Phenomena 51 3.2.3 Scientific Concepts 53 3.2.3.1 Energy 53 3.2.3.2 Heat and Temperature 54 3.2.3.3 Second Law of Thermodynamics and Entropy 55 3.2.3.4 Chemical Equilibrium 55 3.3 Studies in the Commonsense Forms of Reasoning Perspective 56 3.3.1 The Role of Action and Cause 57 3.3.2 Explanation 60 3.3.2.1 Ontology, Causation and Explanation 60 3.3.2.2 The Experiential Gestalt of Causation. 62 3.3.2.3 Linear Causal Reasoning 63 3.3.2.4 Symbolic Knowledge and Life-World Knowledge 64 3.3.2.5 Teleological and Anthropomorphic Reasoning (Explanations). 65 3.3.2.6 Tautological Explanations. 67 Contents - 8 3.4 Studies in the Developmental Psychology Perspective 67 3.4.1 Stavy's Studies 67 3.4.2 Bar's Studies 70 3.4.3 Shultz and Coddington's Study 73 4 The Conception of the Study 4.1 The Choice of Problem 75 4.1.1 The Context of the Study 75 4.1.2 Possible Kinds of Questions to be Raised 77 4.1.3 Relationship Between Different Ways of Thinking about Reversibility 78 4.1.4 Research Questions 81 4.2 The Empirical Work 81 4.2.1 The Pilot Study 82 4.2.1.1 The Choice of Phenomena 82 4.2.1.2 Methodology 83 4.2.1.3 The Instrument 84 4.2.1.4 The Sample and Administration 89 5 Pilot Study - Factor Analysis: A Space of Explanation 5.1 Introduction 91 5.2 Factor Analysis 92 5.2.1 Representations of Phrases in the Factor Space 93 5.3 Interpretation of the Factors 97 5.3.1 Factor I: Can Happen vs. Cannot Happen 98 5.3.2 Factor II: Happens by Itself vs. Needs an Action 99 5.3.3 Factor III: Teleology - Goal vs. No Goal 100 5.3.4 Factor N: Relaxation 100 5.4 Interpretation of the Correlations between Factors 101 5.5 Inspecting the Interpretation of the Factor Solution 102 5.5.1 Events along the dimension I: Cannot Happen vs. Can happen 102 5.5.2 Events along the dimension II: Happens by itself vs. Needs an action 104 5.5.3 Events along the dimension HI: Goal vs. No Goal 107 Contents - 9 5.6 Characterisation of Events According to the Fourth Factor: Relaxation 107 5.7 Summary of Factor Space 110 5.7.1 Summary of the Interpretation of the Factor Solution 110 5.7.2 Summary of the Results concerning the Description of Events 111 6 Pilot Study - Description of Events 6.1 Introduction 112 6.2 Cluster Analysis 113 6.3 Analysis of the Action/Cause Responses 115 6.3.1 A systemic network for analysing the responses 115 6.3.2 The Events: how the students describe them 117 6.3.2.1 PENDULUM - 'a pendulum stops swinging' 117 6.3.2.2 SLOPE - 'a ball rolls down' 117 6.3.2.3 TANK - 'the water flows out' 117 6.3.2.4 PENCIL - Q1 - 'a pencil is worn out' 118 6.3.2.5 TEA - 'a cup of tea becomes cold' 118 6.3.2.6 CHAMPAGNE - 'the champagne goes flat' 119 6.3.2.7 BOMB - 'a bomb explodes' 119 6.3.2.8 CAR - 'a car rusts away' 119 6.3.2.9 BATTERY - 'a car battery runs down' 120 6.3.2.10 PLANT - 'a plant grows' 120 6.3.2.11 WATCH - Q1 - 'the time goes by' 121 6.3.2.12 WHEEL - 'a rotating wheel stops turning' 121 6.3.2.13 JACK IN THE BOX - 'a "jack in the box" jumps' 122 6.3.2.14 EGG - 'an egg is broken' 122 6.3.2.15 PENCIL - Q2 - 'a pencil is worn out' 122 6.3.2.16 ICE-CREAM - 'an ice-cream melts' 123 6.3.2.17 PUDDLE - 'water in a puddle evaporates' 123 6.3.2.18 CANDLE - 'a candle burns away' 124 6.3.2.19 ALKA-SELTZFR - 'an alka-seltzer tablet dissolves' 124 6.3.2.20 MAGNET - 'a magnet attracts nails' 125 6.3.2.21 BOY/MAN - 'a man grows old' 125 6.3.2.22 WATCH - Q2 - 'the time goes by' 125 6.3.3 Reversibility: the description of the events 127 6.3.3.1 Natural process reversed by an action 128 6.3.3.2 Natural process triggered by an action and reversed by an action 128 Contents - 10 6.3.3.3 Natural process with natural reverse 128 6.3.3.4 Non natural process triggered by an action reversed by an action 129 6.3.3.5 Irreversible natural processes 129 6.3.3.6 Irreversible processes 129 6.4 The Clusters according to Actions and Causes 129 6.4.1 First Cluster: Happens by itself, ruled by some causal law 130 6.4.2 Second Cluster: Unlikely to happen 130 6.4.3 Third Cluster: Possible, but difficult to reverse 131 6.4.4 Fourth Cluster: Happens by itself 131 6.4.5 Fifth Cluster: Non natural reversal caused by action 131 6.4.6 Sixth Cluster: Happens naturally due to a planned action 132 6.4.7 Seventh Cluster: Happen with difficulty due to an action taken with a goal 133 6.4.8 Eighth Cluster: Unlikely to happen or possible reversal