What would Ruth Glass do?

This article is a contribution to debates in this journal surrounding the politics of urban epistemology. It uses a close reading of Ruth Glass’ introduction to London: Aspects of Change (1964) to advance a critique of urban knowledge production that suggests urban studies ought better to strive to accommodate the complex and often contradictory qualities of cities rather than seeking to tidy up these phenomena in exchange for clean terms of analysis. The example given in this paper is gentrification studies, which in some ways, fails to learn from the epistemic qualities of Ruth Glass’ essay, in which the term is coined. There is a risk that where academic taxonomy becomes too reified and too mobile it becomes a commodity itself which operates in an epistemology which reproduces the logic of capital. How might urban studies further strive to not only critically engage with cities but to produce ‘emancipatory’ knowledges which work to undermine the dominating logics which produce urban space?

D uring fieldwork in Brixton, I attended a consultation on the topic of the regeneration of a street; a consultant stood and gave a careful account of his research into footfall based on a survey. In response, the owner of a family business that had been on the street for years stood up and explained that whilst he saw that this consultant had done his research he had a different kind of knowledge, one based on generations of presence and commerce on the street. The business owner wanted his knowledge to be recognised as an acceptable and rigorous counterpoint to the knowledge of the consultant. The business owner did not want to discount the data provided by the consultant, instead, he wanted his embodied and longitudinal knowledge to be recognised as 'useful'. These two forms of knowledge represent different but arguably differently valid knowledges of the same space. This moment raised the question explored in this paper: what do you do when you encounter divergent urban knowledges?
Urban studies that resists being drawn into a debate with the consultant but instead captures the radical counter-knowledge of urban life, otherwise too easy to dismiss, would have the capacity to make critical interventions into the politics of the city. In this paper, I argue that a critical urban knowledge must accommodate better the complexity and ambiguity of urban life. Not demanding that we choose which knowledge we accept as 'true', but appreciating that divergent urban epistemologies carry divergent political freight. Situating this within recent debates regarding urban epistemology, I will suggest that Ruth Glass' introduction to London: Aspects of Change (1964) offers an example of such radical urban knowledge. Given Glass' reputation as the coiner of the term 'gentrification', I will then argue that gentrification studies itself illustrates a form of urban epistemology for which we can find an anachronistic critique in London: Aspects of Change. Ultimately this intervention argues that in critical urban studies we must also produce critical forms of knowledge in order to better engage critically everyday urban politics.
The moment in my research described above led me to attend to the political nature of urban knowledge production, a position that Madden has recently made in this journal (2015,301). Debates surrounding epistemology have recently loomed large in the pages of City, and urban studies at large. In the strand of debate that emerged from a cluster of 2015 papers and rejoinders (Brenner and Schmid 2015;Madden 2015;Meagher 2015;Schafran 2015), Madden sets out the urgency of such discussions when he asserts that 'urban knowledge is political' (2015,301). This paper takes this deceptively straightforward claim as its starting point and seeks to move this debate towards the actual work of establishing a practical basis for producing urban knowledge which might produce representations of the city which do not replicate the epistemic assumptions of capitalism. As Loftus' recent article on 'the planetary' has urged, debates need to move beyond another return to structure/ agency but instead advocate for the accommodation of a 'tension between the abstract and the concrete' (2018,93) in the work of urban studies. Loftus here agrees with Meagher's argument that we must avoid 'narrow parochialism, but also the sink holes of totalizing theories ' (2015, 818).
Do we have to construct a betwixt and between, why can't we have both the specific and the general? Meagher usefully introduces the critical theorist Braidotti's concept of the 'nomadic subject' (Braidotti 2011, 2;cited in Meagher 2015, 814) as a model for urban methodology. Braidotti's subsequent work on posthumanism might offer a further provocation to urban epistemology. Braidotti rejects the either/or for a monistic philosophy of complexity, continuity and the and/ and (2013, 35). Here is a model for a truly emancipatory epistemology; which strives to accommodate complexity and contradiction within the way we represent the city. In the following section, I will go on to argue that such an epistemology is epitomised in Ruth Glass' introduction to London: Aspects of Change (1964), a text which is more radical than is usually appreciated when it appears in lists of citations. Glass' essay introduces a volume about London which illustrates a decidedly interdisciplinary approach to documenting the nature of a changing city. Whilst the term gentrification tends to headline any account of this book it would be more representative to make gentrification a footnote to this remarkably multi-faceted document of London in the post-war era, and more vitally, an example of critical urban studies that still includes valuable lessons for the discipline today. This paper positions Glass' essay as a significant critique of contemporary uses of the term gentrification. Shin, Lees and Ló pez-Morales return to Louis Wirth to put forward their view that gentrification studies applied around the world might reveal 'essential characteristics' of cities, whilst at the same time distancing themselves from Glass' perspective (2016, 458;citing Wirth 1938). I want to make a case for rejecting the equivalences sought by Wirth (1938); gentrification as a term of analysis has become a 'superannuated cliché' (Adorno and Horkheimer 1997, 41). Gentrification is descriptively useful, not least because it is often colloquially understood; however, under close attention, the value of the term slips away as it fails to accommodate more complex social relationships than gentrifier/ gentrified (see Bernt 2016). It is not that I want to single out gentrification scholarship in particular; it serves as a case study in a larger challenge to urban studies to pay greater attention to the kind of knowledge we produce. We should be certain that this knowledge does not simply reflect the status quo, but that it opens up radical and emancipatory possibilities.
In a moment where the production of urban knowledge is being incorporated into increasingly complex forms of neoliberal governance via mechanisms such as 'the smart city' (e.g. Batty 2013) there is an immediate imperative for urban studies to advocate for radical epistemologies which not only make an intervention into intellectual debates but the actual governance of urban space. Schindler and Marvin have warned of the 'simplification, datafication, standardised management, comparisons and metrics ' (2018, 9) which are the epistemic basis for an emerging 'logic of urban control' which serves to make cities a more effective technology in the accrual of wealth under capitalism. In the image of the 'smart city' we can observe knowledge becoming a commodity; but we must not rest under the illusion that this is a habit only of capitalist hegemony. When we readily exchange sensuous and irreducibly complex reality for a set of clean equivalences, we copy the trick of capitalism and turn the world into abstract commodity. This article will make a provocative claim that urban studies is guilty at times of producing terms of analysis which operate like commodities, what Shin and Moreno have referred to as 'over expanded urban epistemologies ' (2018, 82). In the fourth section of this paper, I will advance this argument with a specific critique of gentrification studies.
The production of urban knowledge is, as Madden (2015) suggests, a political act, knowledge, therefore, is something that can intervene politically without having to appear to come 'from nowhere' (Loftus 2018, 88). Loftus has critiqued the forms of knowledge production whereby abstractions are 'points of arrival rather than points of departure' (Loftus 2018, 91), but I would emphasise an imperative to retain the strong connections between the abstract concept and the material particularity. Otherwise, there remains a risk that terms of analysis become disconnected commodities subsequently touted around in the name of sustaining the business of academic knowledge production.
A practical model for such 'situated knowledges' (Haraway 1988) can be found for example in approaches emerging from postcolonial theory (e.g. Robinson 2006;Simone 2011;Jazeel 2014) and Queer ecology (e.g. Gandy 2012; Patrick 2014). In the following section I want to suggest that where Gandy describes Queer ecology as 'a challenge to "neatness"' (2012, 742), and where Simone argues for research that recognises where politics is 'enfolded' in the real (2011, 364), they are echoing a practice of urban knowledge making which is pre-empted in Ruth Glass' foundational essay in London: Aspects of Change . Ruth Glass' writings should not be limited to the fading intellectual lineage of gentrification studies, 1 but instead, deserve to be read in the context of more radical geographies of the city.

What would Ruth Glass do?
Ruth Glass' career was consistently overlooked and marginalised. As a woman, a Marxist, a German émigrée, her career faced numerous obstacles. Despite spending her entire life attempting to produce another survey of London Life and Labour (following Booth 1891), these efforts seem not to have been preserved in an archive, certainly not sufficiently catalogued. In the Introduction to London: Aspects of Change (1964) she lays out a radical image of London, her work far exceeds the single word 'gentrification', but the marginalisation which she faced in her career meant that a single word has overshadowed a life of work.
She presents London as a site of constant change, still marred by violence, both the shadows of war and ongoing rapid social change. She is writing in a period in which London is still recovering from the war: 'Though most of the bomb sites are no longer empty, London is riddled with selfinflicted injuries, which cannot be easily patched up' (Glass 1964, xxvi). London at this time was a space of rapid change, of suburbanisation, of economic growth, and it was a source of growing 'fear' what Glass called, 'fear of the giant' (1964, xxvii). The London she describes is stifled by traffic, there are 'armies of commuters ' (1964, xiii), neighbourhoods are 'invaded by the middle classes ' (1964, xviii).
The London Ruth Glass describes is chaotic and complex, it is rife with contradiction, yet these contradictions are not simple polar opposites but the fabric of a shifting and amorphous city whose reality is unpalatable to the mainstream. Throughout the text we are confronted with contradiction: 'diversity of consumption' with 'conformity ' (1964, xiv), the 'juxtaposition of new and old both in the fabric and structure of society' (1964, xiii-xiv), 'social distances [. . .] both shorter and longer'. Glass was very clear that the work of social science entailed the observation of 'contradictory tendencies' (1964, xvi). These ambiguities are not merely a matter of representation, she also makes clear statements regarding the nature of social difference that appear to pre-empt discussions that are still being had today.
One could slip into a rhetoric of polarisation, of a city of extremes, of a stratified urban fabric riven by hierarchy. However she is strongly resistant to the tidying up done by the rhetoric of 'dichotomous terms', not because she doesn't recognise the contradictions in the city, quite the contrary, but because in the use of such constructions as epithets or 'idées fixes' these linguistic moves can 'be accepted as substitutes for more thorough perhaps more unpalatable analyses ' (1964, xxiii). Glass seems to be suggesting that useful research should be challenging, complex, and hard to swallow if it is to succeed at all in reflecting the subject matter. That if you are producing clean crisp terms of analysis then a messy reality is being obscured, in clear contrast to Louis Wirth's 'essential determinants' (1938, 7).
''Conventional terms of social categorisation, such as "black-coated worker" or "white collar worker", no longer have a straightforward descriptive value' Glass (1964, xiv) writes in a clear suggestion that typical class identity was losing its face value. However, she is not surrendering a structural Marxist reading of class position altogether. 'What is happening' she claims, 'is neither an obliteration nor an accentuation of long established class cleavages, but the superimposition of a crisscross web of social divisions, which has as yet been hardly recognised' (xxii). At the heart of Ruth Glass' writing about London is a decidedly sceptical approach to positivist categorisation of the city, a willingness to accommodate contradictory observations and an overall conception of the city as a site of ambiguity.' London for Glass is rife with uncertainty. The rapid changes that are going on in the city that she lives in be it 'gentrification', the homogenisation of culture and consumption, the influx of post-war migrants, who she refers to as 'newcomers' (Glass 1960) are not annihilating the long established cleavages that have shaped the city, but adding to the complexity of social difference as a whole. It is an anachronistic reading of Glass' work, but she might be said to be adopting an intersectional view of society.
Read closely, Ruth Glass' essay is a strong challenge to the epistemological assumptions at work in contemporary urban studies. In an article on the concept of urban conflict her position is made even more explicit, she writes that if an analysis begins with classification 'the beginning may also be the end' (Glass 1989). Were we to apply an ethic of 'what would Ruth Glass do' to the way we construct knowledge about cities, we would be forced to be cautious about efforts to classify and define what we observe.

Emancipatory knowledge
This section builds on the discussion of Ruth Glass' essay by theoretically situating her work as a radical form of knowledge; one which writes with the deftness needed to represent a complex city without ordering it to the point of abstraction. We have already seen the great capacity of her writing to accommodate contradictoriness and mess in the way she describes London. Here I want to suggest that in these epistemic strategies Glass demonstrates how it is possible to produce knowledge which does not lend itself to the kind of commodification which sees even critical analyses reproducing the logics of capital. Instead, Glass demonstrates the possibility of emancipatory forms of knowledge.
Leslie McCall (2005), in her article on the possibility of intersectional methodologies equates intersectionality (Crenshaw 1989) with complexity.
McCall, citing N. K. Hayles (1989), a literary theorist who has written on chaos theory and literature, argues that complexity does not mean unpredictability, and that to jettison 'predictability and linear explanation does not mean that anything goes: reality is complexly patterned but patterned none the less' (McCall 2005(McCall , 1794. However, whilst complex data may contain patterns, the recognition of a pattern is not a definitive act. Talking about scientific laboratory research, John Law has observed the processes by which the researcher faced by 'too much reality to bear' over time begins to discern patterns and similarities that help them navigate-yet the process of seeing '"the right" similarities' is intense and requires the researcher to 'delete "the wrong" similarities and differences' (Law 2004, 107). In complex data, many possible patterns may co-exist. Central to the idea of maintaining a messy epistemology is to try to resist making such deletions and leave such selections to the latest point possible. In her introduction to London: Aspects of Change (1964) Glass accommodates the too-much-to-bear-ness of the city and prioritises the affective quality of the shimmering chaos of London over an effective systematisation of it.
In Dialectic of Enlightenment Adorno and Horkheimer write that 'Bourgeois society is ruled by equivalence. It makes the dissimilar comparable by reducing it to abstract quantities' (1997, 7). Adorno and Horkheimer use the image of Odysseus and the Sirens to explore this. They show Odysseus tearing his self from the danger of total sensuous knowledge in order to subjugate it, and his sailors accepting sensual submission in order to navigate the ocean in clean discrete oar strokes (1997,36). In Glass' writing, there is both a keen reading of structural inequality as well as a sense of the chaotic messiness that the city's fabric presents. Adorno and Horkheimer describe an enlightenment epistemology which produces 'a kind of stock of superannuated clichés, no longer to be distinguished from truth neutralised as a cultural commodity ' (1997, 40) chiming remarkably with Glass' own words about 'idées fixes'. In other words, when you deny embodiment in order to create a dominating form of knowledge you exchange a complex and sensuous 'truth' for knowledge as a transferable commodity. This is the risk inherent in allowing classificatory terms to dominate the way in which we produce urban knowledge.
Returning to Shin and Moreno's description of 'over expanded urban epistemologies' (2018, 82) I suggest that the shift from sensuously tangled knowledge reduced to epistemological commodity in the form of 'idées fixes' has produced the epistemic conditions under which a term of analysis as bloated abstraction ceases to be a means of critique and instead becomes a site of taxonomical competition. In the following section, I will argue that gentrification studies is a case in point. A field whereby a single term has become abstracted from the rich field of observation from which it first emerged. Attempts to maintain the value of this 'superannuated cliché' have led to an urban epistemology in which an eagerness to maintain a point of singular critique-'from nowhere' (Loftus 2018, 88)-has sacrificed the capacity to reflect on the particularities of violence which emerge from the actions of capital in the city.

Gentrification from phenomenon to theory
In this part of the paper, I use gentrification studies as a case study through which to engage critically with the epistemological tendencies of urban studies. This is not to single out this vein of scholarship in particular, but because of Ruth Glass' connection with the term. This paper does not aim to marginalise this work: it has undoubtedly played a huge role in the academic and public critique of how cities develop under capitalist systems, particularly in the global north. But where academic research becomes dominated by the policing of taxonomic boundaries urban studies does itself an injustice.
The origins of the term gentrification are perhaps less clear than we are led to believe. While it is common to cite Ruth Glass as the coiner of the term, when she uses it she places it firmly within inverted commas (1964, xviii). She is talking specifically about the 'doing-up' of 'shabby modest mews and cottages' as previously run down parts of London are 'invaded by the middle classes' (Glass 1964, xviii). There is a cynical humour in Glass' writing, for instance when she sends up the term 'houselets' as part of 'new real estate snob jargon ' (1964, xviii); the term gentrification here, particularly positioned in inverted commas, seems to be the deployment of a colloquial term, even a joke. There is a snideness in the notion that the middle classes are transforming working-class areas into homes for 'the gentry', a joke at the expense of the 'upwardly mobile' aspirations of this cohort. Ruth Glass' use of the term shares more with the description used by the humourist Alan Bennett in a memoir from 1969 when he refers to a neighbour in Hampstead as 'one of the more conventional neighbours (and not a Knocker-Through)' (Bennett 1989). When Ruth Glass uses the term 'gentrification' she is not attempting to produce a cast-iron definition of a sociological phenomenon, but instead to deploy a colloquial-jokey term to characterise one of the many 'aspects of change' in the London she describes.
Ruth Glass' deployment of the term does not spark off an industry of gentrification scholarship: for that, we must wait ten years. Tom Slater has suggested (2009, 295) that Chris Hamnett was the first after Glass to use the term in an academic context in his article on improvement grants (Hamnett 1973). Hamnett's paper refers to specifically geographically bounded phenomena, it does not pre-empt the production of a tightly framed term of classification but instead seems to refer to a colloquial term with which the reader might be expected to be vaguely familiar, and he does not cite Glass. The taxonomical ambiguity of gentrification is made clear when Dugmore and Williams reply to Hamnett's article referring to 'Gentrification, Chelseafication or whatever term is employed ' (1974, 159). At this stage in the development of the term, Hamnett and Williams, who eventually publish together (1980) are carrying out very geographically bounded research; they initially draw little on theory (Hamnett 1973;Williams 1976) and appear to show interest in the very specific conditions of their case studies. The term is vague and the phenomena are specific, it is only later that the term becomes transformed into a tool of academic discipline.
Neil Smith (1979) put forward the rent gap hypothesis and made an intervention that lead to gentrification being considered a generalisable principle rather than a specifically observed phenomenon. Smith wrote '[w]ith the enthusiasm of a second year graduate student I thought to theorise what I was looking at' (Smith 1992, 110). Following Neil Smith gentrification became a phenomenon which was anticipated before it was observed. From this point, the discussion about gentrification that was hosted in journals became dominated by debates as to the proper definition of this newly abstracted theory (Ley 1987;Smith 1987;Hamnett 1991Hamnett , 1992Smith 1992;Hamnett 2009Hamnett , 2010Slater 2006Slater , 2009Slater , 2010. Already this thread of literature was being criticised for its tendency to obscure the 'multiplicity of processes' behind the 'chaotic conceptions' of gentrification and gentrifiers (Rose 1984, 61). I agree with Damaris Rose: it is hard to accommodate the complexity of urban change with one term, and perhaps this was what caused all that bickering around the term.
Ruth Glass' account of the city, for all its heady contradictoriness, is a valuable rejoinder against tendencies in urban studies to over-value the commodity of classificatory terms. Glass's urban epistemology is not entirely absent from gentrification studies; Rose is one example. Another is Liz Bondi, whose incisive critique of gentrification literature (1991) has been too readily categorised as a treatise on gender alone (e.g. Hamnett 2003Hamnett , 2402. In particular, Bondi criticises a tendency to prioritise the abstract and economic over the cultural and to fail to recognise that gender and race are 'inextricably bound up with class' (Bondi 1991, 93). Bondi here echoes Glass' portrait of London as a site of criss-crossed social divides, and of the risk of reducing urban phenomena to abstract 'idées fixes'.
Gentrification studies has long held a steady debate about what exactly it is. Glass was always wary of over-classifying the city, and the rich poetic complexity with which she imbues London in the article that is cited as the origin of the concept of gentrification is an example of how challenging it is to categorise phenomena in a city. The development of gentrification studies demonstrates the great challenges involved in sustaining the universality of a term of analysis as its deployment spreads to different contexts. Perhaps if Smith and Ley had stopped to reflect on the fact that Vancouver and New York are different cities, their debate may have been possessed of a greater sense of camaraderie. This historical account of gentrification studies is relevant because the challenges persist today, recently described by Matthias Bernt (2016) in this journal.
Bernt has warned against dismissing as 'academic hair-splitting' (Bernt 2016, 638) the debates within gentrification studies, now developing around the question of whether the term can be applied in a planetary context (Ghertner 2015;Ló pez-Morales 2015;Lees, Shin, and Ló pez-Morales 2016). Importantly Bernt identifies the fact that gentrification theorists wish to defend 'an indispensable armory for struggles against urban injustices ' (2016, 638). It is important to acknowledge the incisive and powerful forms of critical urban studies which have emerged under the auspices of gentrification studies. In his characterisation of the debate between Lopez Morales and Ghertner as one between the 'very particular' and the 'rather universal', Bernt ultimately suggests that either position helps us to understand only 'half of the story ' (2016, 643). He is in other words, reflecting on the 'contradictory tendencies' (Glass 1964, xvi) of urban space, and the resultant necessity for the 'simultaneous employment of divergent theories' (Bernt 2016, 643).
In reducing Ruth Glass to the term gentrification critical urban studies fails to appreciate the greater value of Ruth Glass' academic research, the epistemology she demonstrates in the way she represents the London. Ironically, gentrification studies is one subdiscipline of urban studies that might particularly gain from re-visiting Glass' work. Bernt makes valuable suggestions for how gentrification studies might learn from the apparent distance between approaches which focus on the particular and those which strive to defend the general, he advocates for further comparative research, drawing on other areas of urban studies, and relating analysis more closely to the commodification of land and housing (2016,643). However, I suggest that there is a deeper issue at hand: returning to the discussion in the first section of this paper, the debates surrounding the universality or not of gentrification as a term of analysis speak to more profound questions of epistemology. Further to Bernt's argument, this paper suggests that in order to produce radical urban knowledge we must produce a form of knowledge that accommodates the ambiguity and messiness that constitutes the city, maintaining the contradictions that emerge when a city is observed from multiple scales and we attempt to speak both about the particular and the general. Ruth Glass's essay introducing London: Aspects of Change is the exemplar of a document that retains certain epistemological messiness and resists the urge to tidy up.

Conclusion
This paper has offered a response to recent debates in City on the topic of urban epistemology, drawing on the writing of Ruth Glass as an example of a radical form of urban knowledge. Using gentrification studies as a case study the paper argues that we run a risk in urban studies of allowing the abstract to dominate the particularities of urban life, but perhaps equally of rejecting the structural at the expense of the everyday. Ruth Glass' essay, discussed here, shows the value of accommodating different scales of observation and complexity in producing a genuinely emancipatory form of knowledge: as Madden has observed urban knowledge is political (2015).
The critique of knowledge that appears to come 'from nowhere' (Loftus 2018, 88) because it aspires to produce abstract and generalisable concepts deserve to be read in the context of academia's current intellectual climate. I have suggested that where we overly classify and 'tidy' the sensuous and contradictory urban life that researchers encounter in their work, we do so to produce knowledge that can operate as a 'superannuated cliché' (Adorno and Horkheimer 1997, 40), this is problematic. If it is the goal of critical urban studies to challenge the dominating and commoditising production of urban space that we observe it is hard to do so if our epistemology is inflected by the same capitalist sensibility. However, where our academic work is judged for its ability to produce social and economic 'impact' and our careers rest on our capacity to maintain something akin to an intellectual brand, how can we create knowledge that is both 'valuable' and truly critical?
In Gandy's account of the queering of spatial theory as a 'challenge to neatness ' (2012, 742), and in Jazeel's call for postcolonial geography to maintain a close connection to 'the world's discontinuous and truly heterogenous textual fabric' (2014, 101), there is a sense that our observations should be vulnerable to the complexity and heterogeneity of what we observe. To produce radical critiques but to continue to perpetuate a dominating epistemology whereby the scholar can claim to truly know what is and what isn't happening, not only in the city they observe but in the observations of others, is a shortcoming. Ruth Glass' observations of London already undermine any static conception of what gentrification is, instead it points to a city that cannot be captured in neat terms, and instead demands a messy, queer, heterogeneous epistemology. Such a knowledge appears at face value to be less 'useful' because it is hard to package up and disseminate. I hope that this paper can add to the calls to produce urban knowledge that accommodates heterogeneity, and I contend that these forms of knowledge will prove to be more valuable not only in the critical edges of academic discourse but in the pragmatic work of producing a good city.
The point of this paper is not to dismiss the value of work done in the vein, for instance, of political economy, nor is it to dismiss the intellectual significance of gentrification studies. Who could deny the perspectiveshaking insight of Smith's rent gap hypothesis (1979)? However, if we are to continue to allow such observations to feature in our analysis of diverse urban landscapes we must not expect that such insight will be total. Instead, I suggest, we forget the neat either/or and adopt an epistemology of the and/and, whereby we do not mistake a debate between the particular and the general for an ideological one but instead recognise that cities are at one scale similar and at others totally different. This makes the work of producing urban knowledge more difficult, but more interesting.
Note 1 Though outside of urban studies her insights into migration are better appreciated. For instance, she has work cited in both Hall et al. (2013) and Gilroy (2002).

Disclosure statement
No potential conflict of interest was reported by the author.