Greg Woodin is a second year English Language student at the University of Birmingham. His interests include psycholinguistics, phonology and pretty much anything to do with words.

Howler monkeys, credit: Wikipedia

‘A vague, uncharted nebula’: disentangling the relationship between language and thought

I 

A Divisive Issue

The relationship between language and thought and the extent to which these factors might influence each other is a central topic within psycholinguistics. Traditionally, it has been argued that thought is not just influenced by language but is contingent upon it, with stronger formulations of this position claiming that without language, thought cannot exist. One notable proponent of this view is Saussure (1966: 112), who asserts that ‘without language, thought is a vague, uncharted nebula. There are no pre-existing ideas, and nothing is distinct before the appearance of language.’ Essentially, this theory contends that language is thought and therefore that the two cannot be disentangled (Müller, 1909). Another similar but weaker position is expressed by linguistic determinism, which argues that although language is a separate faculty to cognition, certain languages ‘predispose certain choices of interpretation’ (Sapir, 1929: 69), exerting control over our cognitive processes and influencing how we perceive reality (Lucy, 1997: 291).

These deterministic views have come under some criticism in recent years, with many linguists instead arguing in favour of linguistic relativity, a weaker formulation of linguistic determinism that posits that, despite not being able to override pre-existing conceptual distinctions, language can ‘augment certain types of thinking’ (Wolff and Holmes, 2011: 253). In this way, linguistic processes might be described as ‘pervasive’, influencing most domains of thought (Boroditsky, 2003: 920).

Determining which of these positions is most convincing would help to shed light on a murky and divisive issue, as well as conceivably signifying something profound about humanity’s place among the other species of the world that are without language; if the evidence suggests that thought is not the exclusive domain of humans, we would no longer seem so supremely rational or distinct from our animal counterparts. Furthermore, if the evidence points towards the notion that language can to some extent influence thought, we might begin to uncover the true power of underlying sexist or otherwise discriminatory language to influence perceptions in society.

In an attempt to do this, I firstly explore the distinction between language and the more primitive communication of animals to ascertain exactly what language is. I then use this definition to examine the argument that language is a prerequisite for thought; if the evidence suggests that animals could think without language, this theory could be fairly dismissed. From this, I conclude that thought must be able to exist in the absence of language. I then investigate the arguments for and against linguistic determinism, before exploring the evidence put forward in favour of linguistic relativity, concluding that this position has the most convincing claims to validity at this moment in time.

II

What is Language?

In order to determine whether thought is possible in the absence of language, it makes sense to investigate the cognitive processes of creatures that do not possess language to ascertain whether these processes might resemble human thought. However, before doing this we must make clear the border between basic animal communication systems and what we consider to be ‘language’. In a list edited down from a longer list of features suggested by Hockett (1963), the criteria for defining language might be distilled into six main features:

1. Semanticity: symbols are used to represent or ‘mean’ objects or actions.
2. Arbitrariness: there is no necessary ‘connectedness’ (Čadková, 2014: 16) between a symbol and the thing that the symbol represents – it is purely conventional. This explains the use of different words in different languages to represent the same concepts.
3. Cultural transmission: language is learnt rather than innate, and is passed down from generation to generation. For instance, parents normally teach their children to speak rather than their children developing language independently of any linguistic stimulus.
4. Spontaneous usage: humans use language freely and voluntarily. This contrasts with, for instance, a chimpanzee producing a food call involuntarily upon discovering a new food source (Deacon, 1997: 224).
5. Displacement: with language, we can refer to concepts that are ‘far removed in time and place’ (Aitchison, 1983: 38), such as the past or future, or people or things who are not in the immediate vicinity.
6. Creativity: humans can use language to produce unique utterances; with language, a person might discuss virtually anything he wishes to – even ‘a platypus falling backwards downstairs’ (Aitchison, 1983: 40).

 

Hockett does not claim that all of these factors are unique to human language; indeed, elements of chaffinch bird song such as pitch and rhythm appear to be taught rather than innate (Thorpe, 1961, 1963), and bees display evidence of displacement when communicating details of a source of nectar that they have discovered (von Fritsch, 1950, 1954, 1967). However, there does not appear to be evidence of an animal communication system that possesses all of these features. Therefore, it might be posited that a communication system must possess all these features to be classed as a language.

By this definition, proponents of the ‘language is thought’ position might conceptualise thought as a watch, an irreducibly complex device that needs all of its constituent cogs and levers to function. This suggests that the fulfilment of all, and only all, of the above criteria creates some kind of magical condition that suddenly enables its user to think. In the next section I explore whether this position is tenable.

III

Language is Thought

The idea that language is identical to thought is attractive for intuitive reasons; most humans possess the ability to speak a language, and it might be proposed that most humans use that language as a medium of formulating their thoughts. Thus, it might indeed be difficult to imagine thinking without the use of words. However, as we have seen, animals are without language, and so if animals were proven to be able to think, the position that thought cannot exist in the absence of language could be reasonably abandoned. Unfortunately for ‘language is thought’ theorists, this is exactly what the current evidence suggests.

Research into apes in particular has provided a wealth of evidence against this theory. For instance, apes use knowledge of their territory to plan routes between food areas (Menzel, 1978), make and use tools (Ulbaek, 1998: 34), and learn through social interaction (Passingham, 1982: 176). In addition to this, apes gain knowledge through ‘studying the actions of others’ (Passingham, 1982: 200), conform to a hierarchy within their social groups (Ulbaek, 1998: 34), and may intentionally deceive their fellow primates (Whiten and Byrne, 1988). Perhaps most impressive of all is that apes appear to treat other apes as having their own individual intentions and thoughts, a faculty of cognition known as ‘theory of mind’ (Premack and Woodruff, 1978). Evidence of cognition can even be found in rats, whose behaviour when running through a maze displays evidence of organised knowledge and cognitive maps, processes that cannot be dismissed as mere habit formation (Tolman, 1932, 1948). All of this points towards the ability of animals to think, suggesting that thought can exist independently of language.

Other arguments put forward against this position are based not on empirical observation but on simple common sense. For instance, the very fact that one can sometimes have thoughts that are difficult to express is surely evidence of thought without language (Pinker, 1994). This phenomenon might be related to so-called ‘tip-of-the-tongue’ states, in which a lexical item that a person is trying to retrieve from memory is temporarily inaccessible (Schwartz and Metcalfe, 2010: 737). Here, because a person is aware of a word’s existence in spite of its inaccessibility, it might be posited that this awareness indicates the existence of extra-linguistic knowledge. Moreover, if people thought entirely in words, words expressing new concepts could not possibly be conceived, because without the word there to begin with, the concept could never be imagined (Wolff and Holmes, 2011: 254). Therefore, it seems that non-linguistic thought must be possible, a faculty of cognition Pinker (1994) terms ‘mentalese’.

Based on this, it might be concluded that ‘language is thought’ is not a defensible position. With this hypothesis disregarded, I now evaluate the concept of linguistic determinism, the argument that although thought can exist without language, it is nevertheless heavily dependent on it.

IV

Linguistic Determinism

Unlike ‘language is thought’, linguistic determinism does not claim that language and thought are identical. Nevertheless, it is still very strong in its claims, positing that thought and perception can be significantly controlled by language, and therefore that people are ‘very much at the mercy of the particular language which has become the medium of expression for their society’ (Sapir, 1929: 69). In this section, I explore whether the strength of these assertions is justified.

One of the most well-known arguments in support of linguistic determinism is Whorf’s appeal to the idea, popularised by Boas (1911: 211), that Eskimo languages have multiple words for different types of snow whereas English has only one: ‘snow’. Whorf suggests that the lack of a distinction between these different types of snow in English would actually limit English speakers’ abilities to perceive the differences between them (Whorf, 1940: 216). This claim is controversial for many reasons. Firstly, there is no actual evidence that Eskimos can perceive more types of snow than English speakers, meaning that this argument is based upon mere speculation (Traxler, 2012: 21). Furthermore, the claim that Eskimo languages have more words for snow appears to be apocryphal, with Eskimo languages having “about as much differentiation as English does for ‘snow’ at the mono-lexemic level” (Martin, 1986: 422), a claim supported by Pullum (1989: 280). Therefore, it seems that this argument at least cannot successfully support linguistic determinism.

Nevertheless, if it were proven that speakers of different languages perceived other aspects of the world differently and this could be correlated with particular differences in their respective languages, this hypothesis would gain a great deal of traction. However, universalities in language and perception have instead been cited to suggest that language may actually represent, rather than depend on, thought. For instance, just as virtually all people share the same physical mechanisms responsible for colour perception (Traxler, 2012: 22), most languages consistently have seven or fewer basic colour terms (Kay and Maffi, 1999). Even in Dani, a New Guinea language with only two colour terms – black (‘mili’) and white (‘mola’) – speakers are still able to categorise other colours in the absence of words for these categories (Heider, 1972). Moreover, a plethora of studies in the field of emotion perception (Berlin and Kay, 1969; Ekman, Sorenson and Friesen, 1969; Hardin and Maffi, 1997; Huang et al., 2009; Kay and Maffi, 2000; Lenneberg and Roberts, 1956) all point towards homogeneity in both perception and linguistic representation of emotion across vastly different languages.

These findings are problematic for supporters of a deterministic position, suggesting that language cannot actually change our physical perception of the world. However, a more moderate version of this argument known as ‘linguistic relativity’ has slowly gained popularity in the linguistic community, which claims that language, while not being able to change perception, may be able to ‘augment’ different types of thinking. Perhaps this can provide a better explanation of the relationship between language and thought.

V

Linguistic Relativity

As we have seen, the current evidence suggests that the relationship between language and thought is much less deterministic than has traditionally been argued; as Wolff and Holmes (2011: 255) contend, ‘the connection between thought and the world is tighter than the connection between thought and language’. However, this does not mean that there is no interplay between language and thought at all. In fact, a host of evidence suggests that language can indeed influence thought, albeit in less extreme but nevertheless profound ways. This is the claim known as ‘linguistic relativity’. In this section, I investigate how language might affect our conceptualisation of the world, aid in the retrieval of information from memory, and increase our so-called ‘brain power’.

Mental representations and conceptualisation

One claim of linguistic relativity is that language can affect our mental representations of different elements of the world, influencing how and what we think about them. This claim has been explored in relation to grammatical gender in language, with German and Spanish speakers being asked to list three adjectives in English (chosen because it is a neutral language without grammatical gender) that described different objects best. These adjectives were then rated as being either masculine or feminine by a group of native English speakers. As predicted, a correlation was found between the perceived femininity or masculinity of these adjectives and the grammatical gender of the object described. For instance, in German the word ‘key’ is masculine, and this grammatical gender was consistent with the rather masculine-sounding words ‘hard’ and ‘heavy’ used to describe this object by German speakers. This contrasts with Spanish speakers, who preferred the more feminine adjectives ‘little’ and ‘lovely’, congruous with the word’s feminine inflection in Spanish (Boroditski et al., 2003).

Of course, it is possible that these findings were the result of cultural factors rather than language; perhaps keys are made harder and heavier in Germany than in Spain. To rule out this possibility, a further study was conducted. In this study, native English speakers were introduced to ‘Gumbuzi’, a fictional language divided into two categories (‘soupative’ and ‘oosative’) that were shown to clearly correspond to biological gender. After participants were exposed to this distinction, these categories were then extended to inanimate objects. Just as was the case in the previous study, participants’ descriptions of these objects were consistent with their respective grammatical genders (Boroditsky and Schmidt, 2000). These results suggest that language can affect our mental representations of the world.

The effect of language on conceptualisation is explored further in Lakoff and Johnson’s (1980) conceptual metaphor theory, the idea that metaphor acts as a kind of ‘imaginative rationality’ that ‘permits an understanding of one kind of experience in terms of another’ (Lakoff and Johnson, 1980: 235). One example of this is the purported ‘spatialisation’ of time, the way time is conceptualised metaphorically in terms of space and direction. For instance, in English it might be typical to ‘look forward’ to a future event, or to ‘move a meeting back’, envisaging the future as ahead and the past as behind (Lai and Boroditsky, 2013: 1-2). This stands in sharp contrast to Mandarin Chinese, where the future might instead be visualised as ‘down’ and the past as ‘up’ (Fuhrman et al., 2011: 1305).

To investigate this phenomenon, both native Mandarin and native English speakers were shown a sequence of images depicting simple temporal progressions – of, for instance, Julia Roberts at different ages, or of a banana being eaten. Participants were then asked to identify the chronological order of these sequences by using the directional pad on a keyboard, a task conducted under two different conditions, one in which the left directional key corresponded to ‘earlier’ and right to ‘later’, and another in which the up directional key corresponded to ‘earlier’ and down to ‘later’. The results showed that Mandarin speakers’ reaction times were significantly quicker than English speakers in the up-to-down task. This suggests that Mandarin speakers conceptualise time vertically, in accordance with vertical spatio-temporal metaphors in their native language (Fuhrman et al., 2011).

These findings are supported by a study investigating speakers of Mian, a language of Papua New Guinea which conceptualises time as flowing in relation to speakers’ bodies (left to right or towards the body) or their landscape (east to west or west to east). In this study, participants were asked to arrange a set of cards depicting simple temporal progressions on the ground in a chronological order. From this, it was found that the direction in which these cards were laid out corresponded to the representation of time in Mian, with speakers presenting the temporal sequences as travelling either left to right across the body, towards the body, or along the east-west axis of their landscape (Fedden and Boroditsky, 2012). These studies suggest that conceptual metaphors in language may have the power to influence the way these concepts are represented in thought, just as linguistic relativity predicts.

Memory and information retrieval

Language may also have some kind of effect on the storage and retrieval of information from memory, another important faculty of cognition. The Pirahã language was studied to test this, a language with very limited numerical system that makes only a rudimentary distinction between ‘a small size or amount’, ‘a somewhat larger size or amount’ and ‘many’. In this study, Pirahã speakers were first presented with a quantity of spools of thread, which they were asked to match in quantity with a set of uninflated rubber balloons. Their performance in this task was not impaired by the absence of specific numbers to describe these quantities, contradicting the deterministic idea that language creates the concept of exact quantity in thought. However, when these spools were dropped one by one into an opaque cup, forcing participants to memorise the quantity of spools, Pirahã speakers were generally inaccurate. This suggests that linguistic representations allow for longer-term retention of exact quantities in memory (Frank et al., 2008). This makes intuitive sense; after all, it is surely easier to remember a number than to maintain a mental image of exactly that number of objects (Traxler, 2012: 24).

The ability of language to aid recall can be observed in shorthand abstractions (SHAs), simplified terms that “stand […] for a cluster of interrelated ideas” (Flynn, 2007: 146), such as ‘placebo’ or ‘market’. SHAs can help people to remember and identify complex concepts more easily; if a language has a ready-made term to express a concept, it is more likely that thought will be guided towards this concept (Hunt and Agnoli, 1991). However, the presence of this linguistic label may negatively affect other aspects of cognition; as Pöppel (2011) argues, humans are victims of “monocausalitis”, and so SHAs may encourage the explanation of an effect on the basis of just one cause when the situation is far more complicated than this. In this way, the simplification of a multifaceted concept into a one-dimensional SHA may foster over-simplified, unrealistic thinking.

Mnemonics are another example of language augmenting memory, with alliterative idioms being more likely to be recollected than other idioms (Boers and Lindstromberg, 2005). Just like SHAs, these mnemonic idioms make the concepts expressed by them more easily retrievable from memory, but, also like SHAs, may negatively affect other aspects of cognition. For instance, mnemonic idioms are likely to be considered more meaningful than non-mnemonic idioms, even if they express the same concept. In one study investigating the effects of rhyme on perceived meaning, participants were shown two forms of an unfamiliar idiom, one with rhyming properties (‘woes unite foes’) and one without (‘woes unite enemies’). Despite perceiving each aphorism as equally comprehensible, participants rated the rhyming version as more accurate (McGlone and Tofighbakhsh, 1999). This phenomenon, known as the Keats Heuristic, is clearly irrational and shows that the aesthetic properties of language can to some degree affect human rationality and judgment, both important faculties of thought.

Bilingualism and foreign language learning

Just as our native language has the capacity to influence our mental representations and memory, the ability to speak more than one language may also affect cognition in ways that are not immediately apparent, increasing ‘brain power’. For instance, evidence from MRI scans suggests that learning languages may actually make the brain increase in size. One part of the brain that appears to grow during language learning is the hippocampus, an area responsible for learning new material and coordinating spatial navigation (Mårtensson et al., 2012). Furthermore, lifelong bilingualism may actually contribute to cognitive reserve, the idea that keeping one’s brain ‘active’ through physical or mental exertion helps to maintain cognitive functioning (Bialystok et al., 2012). This can help to preserve memory and problem-solving faculties of thought, delaying the onset of Alzheimer’s disease and dementia (Craik et al., 2010; Alladi, et al., 2013).

Possessing more than one language may be cognitively beneficial in other ways. For instance, it has been suggested that bilinguals are more rational and utilitarian in their responses to moral dilemmas when using a non-native language, perhaps because foreign languages are more ‘psychologically distant’, reducing the impact of intuitive emotions on decision making (Costa et al., 2014). This is supported by the suggestion that we ‘embody’ less when reading in a foreign language than in our mother tongue. Embodiment is the phenomenon where, when processing emotional information, our body mimics the physiological state typical of that emotion. For instance, a person might smile when reading about a happy person, scowl when reading about someone who is angry, and so on. This effect is significantly diminished when reading in a foreign language, an effect can be observed even in bilinguals who are entirely fluent in both languages (Foroni, 2015). All of this suggests that a bilingual’s native language may encourage emotional, intuitive responses where their second language might instead promote more analytical, dispassionate thinking. The contrasting effects of these languages on thinking is another strong argument in favour of linguistic relativity.

VII

Conclusion

To summarise, arguments put forward in explanation of the relationship between language and thought might best be envisaged as a glass of orange squash. In this analogy, arguments begin too strongly (‘language is thought’) before being slowly diluted, progressing through linguistic determinism and into linguistic relativity. Throughout this process, the squash steadily becomes weaker as more nuanced claims are proposed. However, unlike a glass of orange squash, which becomes clearer and more transparent the more it is diluted, as arguments progress from ‘language is thought’ into weaker formulations, they generally become more opaque and harder to comprehend. Nevertheless, despite being more complex, it seems that linguistic relativity boasts the most convincing claims to validity at this moment in time.

Therefore, based on the consideration of the evidence that is currently available, my conclusion is this: although language is emphatically not identical to thought, and although it does not have the capacity to change our physical perceptions of the world, it can exert some considerable influence over our mental processes. For instance, as we have seen, language can influence our conceptualisation of the world, aid in the retrieval of information from memory and increase our brain power. It must be noted that this is only a small selection of the myriad ways in which language may augment thought; the influence of language on cognition does indeed appear to be pervasive.

This conclusion provides tentative answers to the questions proposed in part I concerning the cognitive differences between humans and other animals, as well as the power of underlying discriminatory language to affect perceptions or beliefs. Firstly, it suggests that there is nothing necessarily special or distinct about humans in terms of cognition; apes in particular exhibit relatively sophisticated thinking, and thought has even been shown to exist in animals as stereotypically mindless as rats. Of course, human thinking is evidently much more developed and mature, but it can be reasonably inferred from this that thinking is not an exclusively human facility. Furthermore, studies confirming the effects of language on mental representations of different objects suggest that discriminatory language could have a very real impact on people’s thoughts and beliefs, but it is not entirely clear whether these results could be extrapolated to conceptualisations of gender and race. In short, this is an area of study that requires further attention.

What can be safely assumed, however, is that language is an all-pervading influence on thought. Irrespective of how subtle its effects may appear to be, language and cognition are inextricably intertwined: language evidently represents thought – our ‘mentalese’ – but in turn can exert its own influence on our cognitive processes. With further research into this topic, we might begin to make firmer conclusions as to the extent of this influence.

 

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