William James

W William James Lucas McGranahan Chicago, IL, USA Definition “Father of American psychology” who pioneered a functionalist and Darwinian approach to the field, popularized the philosophical school of American pragmatism, and influenced the modern study of religion. Introduction: Life and Works William James was born into an affluent family in New York City in 1842. He was the son of a minor philosophical author and brother of acclaimed American novelist Henry James. James studied to be a painter as a teenager but enrolled in Harvard’s Lawrence Scientific School in 1861. He first studied chemistry but quickly switched to anatomy and physiology, which he used as a basis for studying medicine. His education included a naturalistic expedition to South America in 1865–1866, as well as a trip to study the new science of psychology in Germany in 1867–1868. James earned his medical degree from Harvard Medical School in 1869 and was hired by Harvard as Instructor in Physiology in 1872. He taught physiology, psychology, and philosophy at Harvard before retiring in 1907. As a Harvard faculty member James was instrumental in establishing psychology as a professional discipline in the United States. Known as the “father of American psychology,” James taught the country’s first physiological psychology course in 1875, supervised its first dissertation on a psychological topic in 1878, and published its first important treatise on psychology, The Principles of Psychology, in 1890. James’s Principles is distinguished from prior psychologies by its “positivist” methodology, that is, its emphasis on observable correlations and eschewal of unobservable spiritual entities. This methodology, combined with its Darwinian perspective, makes it a distinctively modern psychological text. Along with its abridged version, Psychology: Briefer Course (1892/1985b), James’s Principles was the key textbook in the field for a generation. Finally, James’s psychology laboratory at Harvard, founded in 1875, was also arguably the country’s first. (James’s student G. Stanley Hall is sometimes given this honor for his later, but more advanced, laboratory at Johns Hopkins University.) Although The Principles of Psychology made James a respected academic, he was also a radical, eclectic, and popular thinker. During the 1890s, James distanced himself from laboratory psychology and championed the study of esoteric abnormal psychology and paranormal phenomena. At the same time, he increasingly lectured # Springer International Publishing AG 2018 J. Vonk, T.K. Shackelford (eds.), Encyclopedia of Animal Cognition and Behavior, https://doi.org/10.1007/978-3-319-47829-6_463-2 2 on philosophical topics such as truth, metaphysics, and religion. His 1897 book The Will to Believe defends the right to hold certain improvable beliefs, and his 1902 book The Varieties of Religious Experience is a seminal text in the psychology of religion. In the final stage of his career, James elaborated his metaphysical doctrine of radical empiricism, which holds that minds and their objects are functions of a more basic reality that is neither objective nor subjective. In parallel, he put forth his philosophy of pragmatism, which holds that the meaning of a concept consists in its practical effects, such that true ideas are just those that “work” in experience. Pragmatism was further developed by another American psychologist and philosopher, John Dewey, who made it the dominant philosophical school in the United States through the end of World War II. James died of heart failure in 1910, having achieved international fame in multiple fields of study. An Education in Evolution Evolutionary biology was formative for James in several ways. First, James matriculated at Harvard soon after Darwin published On the Origin of Species (1859), introducing the theory of natural selection, or evolution by the differential survival and reproduction of different organisms with different heritable traits. James learned about Darwin’s theory from leading scientific minds at Harvard, such as zoologist Louis Agassiz, botanist Asa Gray, and anatomist Jeffries Wyman. James even accompanied Agassiz on an expedition to South America, although he ultimately rejected the latter’s dogmatically antiDarwinian position. Second, James belonged to the storied “Metaphysical Club,” a discussion group that centered on Harvard in the 1870s and included seminal American philosopher Charles Sanders Peirce and future US Supreme Court justice Oliver Wendell Holmes, among other luminaries. Evolutionary debates were central to the Metaphysical Club, with philosopher Chauncey Wright in particular William James pushing James toward Darwinism. Wright published little himself, but he was an important forerunner of James’s Darwinian psychology (1873). Third, James discussed the topic of evolution from the very outset of his publishing career. This includes anonymous reviews of Darwin’s supporter Thomas Henry Huxley, natural selection’s co-discoverer Alfred Russell Wallace, and Darwin himself. James also applies Darwinian concepts to the study of human psychology and history in his earliest signed scholarly essays beginning in the late 1870s. Finally, and most importantly, James boldly supports natural selection in his Principles of Psychology, an impressive survey of the burgeoning science of mind that he wrote between 1878 and 1890. From Lamarckism to Darwinism Darwinism was not taken for granted in psychology during James’s time. Darwin’s principle of natural selection did not achieve its current status as an essential biological principle until the 1930s, when it was integrated with Mendelian genetics and defended using new statistical methods. James’s advocacy for natural selection therefore occurred during a period of uncertainty for the theory, as it competed against other evolutionary and nonevolutionary accounts of mind and life. A case in point is English writer Herbert Spencer (1820–1903). Spencer was the most important evolutionary psychologist prior to James. Indeed, Spencer published his evolutionary theory prior to Darwin’s, which ultimately included an evolutionary account of mind, life, society, and the cosmos as a whole. It was Spencer who familiarized the general public with evolutionary ideas, coined the phrase “survival of the fittest” (for Darwin’s theory), and gave currency to the very words “evolution” and “environment.” The first edition of Spencer’s Principles of Psychology (1855) in particular represents a key compromise between two traditional philosophical views: one that grounds knowledge in innate cognitive structure (as in Immanuel Kant) and another that traces knowledge to the acquired William James sensory experience of the individual (as in David Hume). Mind for Spencer is innate at one level but acquired at another: Innate structure derives from evolutionary processes, and the individual builds upon this structure during development. Such a compromise, broadly construed, is taken for granted in psychology today. What is not taken for granted is Spencer’s preferred evolutionary mechanism. Following Jean-Baptiste Lamarck (1809), Spencer posited evolution by the inheritance of acquired characteristics. This means invoking the population’s collective transformation, whereas natural selection invokes its selective sorting. To use a classic example, Lamarck explains the giraffe’s height in terms of the parallel (and heritable) efforts of all giraffes to stretch their necks, whereas Darwin explains this trait by the survival and reproductive success of those giraffes lucky enough to be taller than average. Similarly, according to Spencer, mind evolves as individuals continually get better at mapping the complex external world and pass on these cognitive gains – physiologically, not just culturally – to their offspring. Lamarckism and natural selection are compatible in principle. In fact, both Spencer and Darwin accepted both mechanisms, while disagreeing about their relative importance. In contrast, James prefigures twentieth-century biology by rejecting Lamarckism completely in the final chapter of The Principles of Psychology. Here James argues that natural selection can explain any trait explained by Lamarckism, and indeed that Darwinian nondirected variation must have been present in cognitive evolution (in contrast to Spencer’s tenet that evolution is linear and fated). Additionally, James favorably cites German biologist August Weismann, whose theory of heredity prefigured the “central dogma” of twentiethcentury genetics by denying that information can flow back to the genetic material during development in a systematically adaptive and heritable fashion. James concludes that natural selection is necessary for explaining mental evolution but that Spencer’s Lamarckism is neither necessary nor plausible. This made James the first important psychologist to adopt an overtly Darwinian (and non-Lamarckian) approach. 3 The Emotions One of James’s most cited positions is his theory of the emotions. During the 1880s, James and Danish physician Carl Lange independently formulated a similar account of the nature of emotion. An intuitive or commonsense view holds that an emotion is a mental perception or judgment, upon which certain recognizable physiological changes may follow. James reverses this logic: My thesis on the contrary is that the bodily changes follow directly the PERCEPTION of the exciting fact, and that the feeling of the same changes as they occur IS the emotion. . . the more rational statement is that we feel sorry because we cry, angry because we strike, afraid because we tremble. (1884, pp. 189–190). James thus contends that emotions just are the experience of certain physiological changes. Upon seeing a bear on a hiking trail, one’s fear consists in one’s perception of certain physiological “fight or flight” responses, after these responses had already been triggered. James’s position on the emotions, in combination with his general skepticism of dichotomies such as emotion/reason and mind/body, prefigure the idea of embodied cognition that arose toward the end of the twentieth century. A critique of James’s position is that the same bodily states may correlate with different emotions, or that different people may express the same emotions differently. This suggests that an emotion is a cognitive judgment preceding the relevant physiological changes. According to James, however, if emotion were defined solely in cognitive terms, this would mean that one could experience an emotion without any given set of bodily sensations. Such an intellectual definition of emotion is too bloodless and spectral, on James’s view. Reflex Action, Will, and Freedom Central to James’s psychology is the nineteenthcentury physiological conception of the “reflex arc” or “reflex action.” According to this model, the sensorimotor system comprises an arc or – as 4 John Dewey (1896) would insist – a circuit in which sensation, cognition, and behavior are defined in terms of their functional interrelations. A nervous impulse is triggered by a sensory stimulus, which in turn triggers cognitive processes that discharge in an associated action. Sensation and cognition are in this sense for action. This is a source of James’s notion that belief, truth, and knowledge should be understood as essentially practical in nature. James portrays the entire reflex arc as a hierarchical series of filters that each sort material provided by the layer beneath: Sensation selectively registers stimuli from the external world; perception selectively eliminates and foregrounds certain features of objects; cognition selectively emphasizes various aspects of situations or ideas for logical, practical, and aesthetic purposes; and the will is capable of selecting among possibilities for action. This last point is key to James. Reflex action may occur automatically along neural paths of least resistance, in which case it is called “ideo-motor action.” James denies that all action is ideo-motor, however, because he contends that individuals can actively bias their actions through acts of will: Options for action filter up from lower levels of perceptual and cognitive processes, and one selects an option by attending to it such that its associated motor consequences automatically follow. James denies that the will’s selections are predetermined, and in this sense he believes the will to be free. (He considers this position to be neither provable nor disprovable, empirically.) James intends this position as an explicit rejection of the “conscious automaton theory” of his time, which claimed that human consciousness has no efficacy in the world. According to Thomas Henry Huxley, for instance, consciousness is like steam escaping from a train whistle, which does not reach back down into the engine to do any work. James denies this. However, his concept of free will is a constrained one, since it does not allow the individual to invent behaviors wholesale. Interestingly, selection appears in this story at multiple levels and timescales. First, James argues that conscious awareness would not exist if it did William James not serve some evolutionary function. James thus makes a Darwinian argument for individual agency, which is ironic given Darwinism’s reputation as an inhuman and mechanistic view of nature. Second, the will’s function in development is similar to that of the environment on Darwin’s theory, since it is capable of selecting possibilities but not creating them. The same is true of each level of selection in the reflex arc, since each merely filters material provided from elsewhere. Finally, the entire reflex arc generates behavioral variation that is tested out against the external world. It was James’s student Edward Thorndike who proposed the “law of effect,” that is, the tendency of behaviors to be repeated if they produce a satisfying result (1898). This law provided a formal basis for behaviorist theories of reinforcement or conditioning that became dominant in the twentieth century. James consistently argued that individuals have agency within their own lives and within the social and natural environments that embed them. Like his godfather Ralph Waldo Emerson, James is known as a classic American individualist. Unlike Emerson, however, he defended this position from a physiological and Darwinian perspective. In particular, James framed his position in contrast to Herbert Spencer’s view that both ontogeny and phylogeny are processes of coercive molding in which organisms are shaped by an autonomous environment. James argued instead that organisms co-construct their environments in evolution and that humans similarly co-construct their societies in history (James, 1897/1979, pp. 163–195). Darwin’s great conceptual advance, according to James, was the idea of variation that is produced for no environmental reason. Natural selection thus drives a logical wedge between organism and environment – a wedge that does not exist for the Lamarckian who construes adaptations as direct responses to environmental demands (James 1897/1979, p. 168). For James, this nondirected variation was emblematic of the idea that nature may contain relatively independent systems that interact in a complex fashion without any one factor completely controlling the output. In contrast, many neo-Darwinians are closer to William James Spencer in viewing evolution as a process of coercive environmental shaping in which individual organisms play a negligible role. Habit, Morality, and the Self According to James, the essence of moral action is the selection of behaviors that restructure one’s habits in the direction of an ideal self. Inspired by the moralistic physiological writings of Alexander Bain and William Benjamin Carpenter, James portrays the self as a plastic bundle of habits that can be altered through the strengthening or weakening of nervous channels. The habitual structure of the self then becomes a long-term artistic and ethical project. The goal of this project, in James’s words, is “to make the nervous system our ally instead of our enemy” (James, 1890/1981, p. 126). In this context, instinct can be viewed as a special kind of habit. James is known for having posited a great number of human instincts – and even for claiming that humans have more instincts than other animals – but he operated with a somewhat deflated concept of instinct. An instinct for James is just a seemingly goal-oriented behavior that did not have to be learned. Strictly speaking, it is only an instinct upon first exercise, at which point it takes its place as a plastic habit among others. It need not even be immutable or universal within a species. James describes habit as an essentially conservative agent. This has advantages: The batter in baseball swings more efficiently when the relevant sequence of muscular contractions fires off in an unconsciously associated chain. On the other hand, the conservative nature of habit also means that one constantly finds oneself stuck in what mappers of evolutionary space call a “local optimum” – an adaptive state that has proved good enough or better than readily available alternatives, but which could be surpassed. The continual surpassing of locally optimal habitual states is thus available as a goal for moral self-cultivation. James promotes his vision of moral development in The Principles of Psychology (1890/1981) and in his pedagogical 5 lectures Talks to Teachers on Psychology (1899/ 1983). The key difference between these texts is that in the Principles James focuses on how one can direct one’s own development, whereas in Talks to Teachers he focuses on how teachers can inculcate useful habits in their students. Although James’s pedagogical theory focuses on the shaping of students’ behavior, it should not be conflated with the behaviorism that overtook psychology after his death. Behaviorism is essentially “outside-in” in its explanatory structure: External stimuli cause behavior through a process of conditioning. In contrast, James critiqued an excessive emphasis on external factors, positing complex feedback between individuals and their environments. According to James, individuals are inherently idiosyncratic, spontaneous, and capable of making free choices. He thus believes that education requires intuitive social and emotional skills, not just rule-based conditioning. James thus construes the self as a plastic bundle of habits that is structured by a reflex arc and mediated by a selective will. Such a self is subject to education and moral improvement. James also sketches several further layers of the self that go beyond physiological psychology: the material self, including one’s body, clothes, property, and the fruits of one’s labor; the social self, defined by one’s recognition from others; the pure ego, which may be a soul or transcendental source of identity; and the spiritual self, defined by one’s direct experience of the stream of consciousness. The Stream of Consciousness The stream of consciousness – called “the stream of thought” in The Principles of Psychology – is one of James’s most influential concepts. According to James, introspection reveals five key characteristics of conscious experience. Thought is (1) always part of a personal consciousness (“my thought”); (2) always changing; (3) continuous; (4) always dealing with objects other than itself; and (5) always interested in some features of its objects more than others. Consciousness is a continuous, ever-changing flux that gives rise to selectively biased thoughts, 6 images, and feelings. This flux, while experienced as “mine,” always posits objects that transcend it. This analysis of subjective awareness has influenced both popular culture and the European philosophical tradition of phenomenology – the study of the essential structure of consciousness – including its founder Edmund Husserl. Notably, the phrase “stream of thought” reflects the third characteristic of consciousness. James’s point here is that thought is like a stream rather than a train. Experience may be analyzable into discrete ideas, feelings, and images, but this does not mean that such elements are the constituent building blocks of experience. On the contrary, James argues that such “simple ideas” posited by classical empiricists are actually refined products of abstraction. James instead likens consciousness to a continuous flux out of which a tissue of mental elements and their relations resolves. In this stream of consciousness, the transitive “flights” of experience (feelings of logical, spatial, or temporal relation) are just as real and just as basic as the substantive “perchings” (abstract concepts and perceived objects), although the mind tends to suppress the former and foreground the latter (James, 1890/1981, p. 221). James’s analysis of the stream of consciousness includes an influential account of temporality or the experience of the passage of time. According to James, the experience of the present moment has a structure in which one senses a stretching forward into the future and a simultaneous stretching backward into the past. James calls this the “specious present” (James, 1890/ 1981, p. 573). For James, the idea of an instantaneous present moment standing precisely between the future and past is a mathematical fiction that is never experienced in actuality. This means that the continuously flowing stream of consciousness is not anchored to a precise, isolable present moment. Radical Empiricism James considers his doctrine of radical empiricism to be essential to his philosophical vision. This doctrine comprises several philosophical William James principles. The first principle is “fallibilism” or the view that all beliefs are subject to correction by future experience. Fallibility is a familiar concept within the philosophy of science, but James applies this principle broadly to entire philosophical and metaphysical worldviews. One’s very concept of the nature and function of science, for James, should be open to correction by experience. The second principle is “pluralism.” On this view, the entire universe cannot be known in a single cognitive act, even in principle. Knowledge is inherently piecemeal, and the world contains systems that hang together in a loose and indeterminate fashion rather than cohering in a fully rational, deterministic matrix. James’s father had been among the “monists” who oppose this view, arguing that the universe is a coherent and selfdeveloping rational whole. This was a common position among idealist philosophers who developed aspects of the writings of Immanuel Kant during the nineteenth century. The final principle of radical empiricism is that philosophy must be grounded in direct experience. As in his account of the stream of consciousness, James considers both discrete objects and the relations among them to be equally matters of direct experience. Reality for James is a flux rather than a set of independently existing beings. In particular, James denies that a permanent and stable thinking entity is accessible to experience. He thus concludes that “consciousness does not exist” (1976/1912), which is his provocative way of stating that the transcendental consciousness posited by certain philosophers does not exist. The very subject-object distinction for James is a derivative function of a more basic reality called “pure experience.” Knowledge then consists of functional relations within pure experience. This position dissolves a basic philosophical dichotomy between the knower and the independent object that it knows. In doing so, it sidesteps a basic problem for traditional accounts of cognitive representation: How does one corroborate the mind-independent nature of objects if they can be only known through some act of knowing or other? James’s position also introduces puzzles, however, such as how two minds could possibly William James know the same object if it did not exist independently prior to any act of knowing. Religion and the Will to Believe James was a prominent scholar of religion, most famously in his Varieties of Religious Experience (1902/1985a). James’s Varieties is not a study of religious dogma or institutions but of religion as experienced by the individual. Moreover, James understands religion very broadly, as one’s overall way of relating to the universe. He spends much of the Varieties describing a series of religious personality types, arguing finally that the “saintly” type – defined by altruistic love and a sense of merging with a higher power – represents the ideal personality. James’s discussion of religious conversion in the book influenced the recovery philosophy of Alcoholics Anonymous. The book also introduced James’s concept of a “moral equivalent of war” or the idea of enlisting youth into civic projects rather than the military, which influenced Depression-era public works projects and the Peace Corps in the United States. James was not just a scholar of religion but one of its defenders. In particular, he argued consistently throughout his career that it is sometimes permissible to hold religious beliefs in the absence of evidence. James likens belief to a bet that one is free to undertake at one’s own risk. For instance, he argues in his essay “The Will to Believe” (1897/1979) that an improvable belief may be justified if (1) the belief is psychologically possible, (2) the question is logically forced or unavoidable, and (3) the result has momentous consequences. James thus contends that a religious belief may be warranted if it creates a shift in one’s moral energies for the better. He also argues, using a similar logic, that one is entitled to believe that the world is morally improvable, if only because this belief may encourage the improvement of the world. James thus viewed religion and belief in general in terms of their functions within the broader scope of human concern. He formalized this outlook in his philosophy of pragmatism. 7 Pragmatism James was the chief popularizer of pragmatism, America’s first philosophical school of international consequence. James’s pragmatism comprises a theory of meaning and a theory of truth. James adapts his theory of meaning from Charles Sanders Peirce. Peirce defined the meaning of an object in terms of its conceivable practical effects (1878, p. 293). James takes “practical effects” in a very broad sense, including dispositions for action. Thus, James defines the meaning of an object – or theory or worldview – by its conceivable effects on sensation, cognition, and behavior. He also claims that a dispute between competing theories is meaningless unless there is a “difference that makes a difference,” that is, a conceivable difference in someone’s experience if one were true rather than the other. James’s theory of meaning underlies his pragmatist theory of truth (which James called “humanism”). On this view, a belief is true to the extent that it “works,” where any number of factors – including but not limited to traditional scientific verification – may contribute to a belief’s working. Thus, meaning consists in practical effects, and truth consists in having good practical effects. This is a highly unorthodox position within the philosophical tradition, as it treats “truth” as an umbrella term for beliefs that turn out to be useful, rather than an explanation for why a belief is useful. As with James’s doctrine of the will to believe, pragmatism is sometimes accused of promoting wishful thinking. The pragmatist would seem entitled to believe anything that sounds good. However, James underscores the essentially conservative nature of individual and social belief systems, which holistically constrain our beliefs. He also claims that truth is inherently open-ended and historical – that is, fallible – such that we can never claim to have arrived at a final or absolute truth. James takes the long view, and he spurns dogmatism in all of its forms. To say that truth is historical for James is not merely to say that we discover different truths at different times. More radically, it is to say that truth itself is inherently dynamic rather than 8 static. In James’s words, “Truth happens to an idea. It becomes true, is made true by events. Its verity is in fact an event, a process: the process namely of its verifying itself” (1907/1975a, p. 97). James thus collapses the conventional philosophical distinction between truth (a static relation between a knower and known) and justification (a temporal process in which truth is discovered). A belief’s truth for James is its justification. Both mind and truth evolve, on James’s view. Whereas in The Principles of Psychology (1890/ 1981) James describes the biological evolution of cognition, in Pragmatism (1907/1975a) and The Meaning of Truth (1909/1975b), James portrays truth as undergoing its own social or cultural evolution. This is not simplistically to identify truth with those beliefs that support Darwinian fitness. Rather, James views truth as having its own selection process that is driven by a host of human purposes going beyond survival and reproduction. Conclusion William James ushered in a physiological, Darwinian, and functionalist approach to psychology. James’s central philosophical concept, however, was the reality and value of individual agency. James thus approached science from a humanistic and explicitly moral perspective. Indeed, Darwinism for James signified a scientific vindication of individual freedom, based on the premise that consciousness would not have evolved by natural selection if it had no efficacy in the world. The will for James is a name for consciousness’s function of selecting ideas that represent possible actions. These selections are capable of altering both the external environment and the internal habitual structure, and the individual may undertake this process with a goal of moral self-cultivation. This process of moral development also provides the framework in which James understands belief, religious or otherwise. His philosophy of pragmatism follows this lead, construing meaning and truth in terms of a range of practical effects. Evolution here appears at multiple levels in William James James’s thinking, both as the origin of our cognitive powers and as a process of social evolution in which truth itself is developed according to myriad values and ideals. Darwin’s principle of nondirected variation also inspired James to think of nature in general as a collection of indirectly related complex systems rather than a rationally comprehensible whole. James’s radical empiricism is comprised by such a principle of pluralism, in combination with a fallible approach to knowledge and a commitment to grounding theory in direct experience. In short, the twin lessons of Darwinism for James are the reality of individual agency and the fallible and piecemeal nature of knowledge. On James’s view, the world and human knowledge are in the making, with individuals as active participants. Cross-References ▶ Alfred Russel Wallace ▶ Behaviorism ▶ Chance and Law ▶ Charles Darwin ▶ Cognition ▶ Consciousness ▶ David Hume ▶ Edward Thorndike ▶ Embodied Cognition ▶ Ethics ▶ Evolution ▶ Evolutionary Psychology ▶ Functionalism ▶ Goal-Directed Behavior ▶ Habituation ▶ Herbert Spencer ▶ Homo Sapiens ▶ Immanuel Kant ▶ Jean Baptiste Lamarck ▶ Laboratory Research ▶ Law of Effect ▶ Mutations ▶ Natural Selection ▶ Nervous System, The ▶ Ontogeny ▶ Phylogeny William James ▶ Reinforcement ▶ Self-Directed Behavior ▶ Sensory Processes and Perception References Darwin, C. (1859). On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. London: John Murray. Dewey, J. (1896). The reflex arc concept in psychology. Psychological Review, 3(4), 357–370. James, W. (1884). What is an emotion? Mind, 9(34), 188–205. James, W. (1975a). Pragmatism. Cambridge, MA: Harvard University Press. James, W. (1975b). The meaning of truth. Cambridge, MA: Harvard University Press. James, W. (1976). Essays in radical empiricism. Cambridge, MA: Harvard University Press. (Original work published 1912). James, W. (1979). The will to believe and other essays in popular philosophy. Cambridge, MA: Harvard University Press. (Original work published 1897). 9 James, W. (1981). The principles of psychology (Vol. 1–2). Cambridge, MA: Harvard University Press. (Original work published 1890). James, W. (1985a). The varieties of religious experience. Cambridge, MA: Harvard University Press. (Original work published 1902). James, W. (1985b). Psychology: Briefer course. Cambridge, MA: Harvard University Press. (Original work published 1892). James. W. (1899). Talk to teachers on psychology: And to students on some of life's ideals. Cambridge, MA: Harvard University Press. (Original work published 1899). Lamarck, J. B. (1809). Philosophie zoologique. Paris: Dentu. Peirce, C. S. (1878). How to make our ideas clear. Popular Science Monthly, 12, 286–302. Spencer, H. (1855). The principles of psychology (Vol. 1–2). London: Longmans. Thorndike, E. L. (1898). Animal intelligence: An experimental study of the associative processes in animals. New York: Columbia University Press. Wright, C. (1873). Evolution of self-consciousness. The North American Review, 116(239), 245–310.