Philosophy of Psychology. Lisa Bortolotti
do, is to introduce the field of philosophy of psychology with some examples of the questions it asks. Philosophy of psychology is the discipline in philosophy that asks the questions we mentioned above concerning rationality, self-knowledge, free will and responsibility, moral judgment, moral motivation and behaviour, and so on.
Below, we clarify what philosophy of psychology is by contrasting philosophy of psychology with two related areas of philosophy, philosophy of mind and philosophy of science, and then distinguishing two approaches to the philosophy of psychology: the first approach is mainly concerned with the theoretical and conceptual foundations of psychology and the second approach is mainly concerned with the implications of psychological studies for philosophically relevant issues.
Philosophy of Psychology and Philosophy of Mind
Philosophy of psychology can be thought of as a sub-area of philosophy of mind, where ‘philosophy of mind’ is understood very broadly as the philosophical exploration of the mind. The focus of mainstream philosophy of mind, which is sometimes called ‘metaphysics of mind’, has been on metaphysical issues of the mind, including the mind–body problem, mental causation, physicalism, and the nature of consciousness. Philosophy of psychology, in contrast, focuses on the kind of issues that are closely related to empirical studies of the mind or the kind of issues on which we cannot make progress without relevant empirical input. When philosophy of psychology addresses human rationality, for example, it examines the available empirical data to find out whether humans actually reason in accordance with the norms of rationality.
Philosophy of Psychology and Philosophy of Science
Philosophy of psychology can also be thought of as a sub-area of philosophy of science, where ‘philosophy of science’ is understood very broadly as the philosophical exploration of science. Philosophers of science study what a theory is, investigate applications of scientific method, and ask whether scientists make progress. Central issues in philosophy of science, or ‘general philosophy of science’, are not essentially connected to a particular scientific field (although many of the traditional issues in philosophy of science are explicitly or implicitly associated with the physical sciences). A recent trend in philosophy of science, however, is the growth and development of those sub-areas that deal with issues that are specific to a particular scientific field. For example, philosophy of biology discusses philosophical issues that emerge from biological studies (e.g., the issues related to adaptationism, the concept of ‘function’ in biology, the level of selection, etc.). Philosophy of psychology is another sub-area that discusses philosophical issues that emerge from psychological studies.
Foundational and Implicational
We find it useful to divide philosophy of psychology into two sub-areas: ‘foundational philosophy of psychology’ and ‘implicational philosophy of psychology’.
Foundational philosophy of psychology is concerned with core concepts in psychology (e.g., ‘representation’, ‘computation’, or ‘concept’) and general hypotheses in psychology that can make sense of a series of relevant studies as interconnected, including: the massive modularity hypothesis, which roughly says that our mind is composed of ‘modular’ systems that are dedicated to some specific tasks (Fodor 1983); the language of thought hypothesis, which roughly says that our cognition is based upon processing language-like representations (Fodor 1975); and the adaptive unconsciousness hypothesis, which roughly says that a part of our mind has evolved via natural selection and we do not and cannot have direct access to it (Wilson 2002). Questions in foundational philosophy of psychology include: ‘What are representations?’, ‘How does computation work?’, ‘Is the massive modularity hypothesis plausible?’, ‘Is the language of thought hypothesis needed to explain cognition?’, and so on.
In contrast, implicational philosophy of psychology focuses on the results of particular psychological studies (rather than their theoretical foundations) and investigates their implications for issues that are philosophically relevant. For example, Chapter 1 will focus on a series of influential studies on reasoning biases (Kahneman, Slovic, & Tversky 1982; Tversky & Kahneman 1974) exploring the implications of such studies for questions concerning human rationality. It will ask, for example, whether these studies show that humans are irrational after all. Chapter 7 will discuss studies on the limitations of memory (Loftus 2003; Schacter & Addis 2007), which show that human agents can easily misremember even important details of past events and thus might have important implications for eye-witness testimony in forensic settings. One might subsequently ask whether these studies show that eye-witness testimony is fundamentally unreliable.
Although we think that the distinction between foundations and implications is useful, we do not assume that it is clear-cut. The difference between them is probably a matter of degree: for example, some issues are more foundational and less implicational than others. There will be some borderline cases. For example, the dual-process theory (the theory according to which there are two distinct types of cognitive processes: Type-1 processes that are fast, unconscious, and automatic, and Type-2 processes that are slow, conscious, and controlled), which is discussed in Chapter 3, might be a borderline case.
Both dimensions of philosophy of psychology are equally important, but this book is more focused on implicational philosophy of psychology than foundational philosophy of psychology. There are two reasons for this. First, implicational issues have recently stimulated very lively discussions in philosophy of psychology research (which used to be dominated by foundational issues). We wanted this book to reflect this recent trend. Second, existing philosophy of psychology textbooks mainly focus on foundational issues, leaving the implications largely unexplored. This book is motivated by our frustration with the lack of accessible resources for discussing implicational issues. Hereafter, ‘philosophy of psychology’ means implicational philosophy of psychology.
This book will focus on implicational issues rather than foundational issues; however, strictly speaking, its focus is even narrower. There are so many interesting implicational issues and one book is not able to cover them all. As hinted previously, we will prioritize topics related to the ‘imperfection’ of human cognition and agency. Our central topics will include reasoning, judgment, belief, emotion, behaviour, and agency. For this reason, unfortunately, we will largely ignore the issues concerning consciousness, perception, attention, and so on. (See Further Resources for some material on the issues that we do not discuss in this book.)
Why Do We Need Philosophy of Psychology?
Why do we need philosophy of psychology, in addition to metaphysical philosophy of mind and psychology as distinct disciplines? Why can’t philosophers confine themselves to purely metaphysical issues? Why can’t psychologists confine themselves to purely empirical investigations?
There has been no sharp distinction between philosophy and psychology in Western intellectual history. Many philosophers who talk about mind and cognition in the history of philosophy go beyond the field of philosophy of mind in a narrow sense and touch on issues that now belong to the field of psychology, for example: Plato’s tripartite theory of soul (according to which the soul is divided into reason, spirit, and appetite) in The Republic; Descartes’ physiological analysis of various emotions in Passions of the Soul; Hume’s associationist psychology in A Treatise of Human Nature; Kant’s classification of mental disorders in Essay on the Maladies of the Head, and so on. The sharp distinction between philosophy and psychology is a modern development, mainly due to the specialization of each field. The advancement of research in each field obliged some researchers to focus on the metaphysical issues of the mind, and other researchers to dedicate themselves to empirical investigations instead. This is an inevitable and perhaps good development overall, but it