Text Matters, Number 14, 2024
https://doi.org/10.18778/2083-2931.14.08
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Dwelling in the Urban Liminal: A Phenomenological Consideration of Saul Leiter’s Street Photography

Satarupa Sinha Roy

Dewan Abdul Gani College, India
Orcidhttps://orcid.org/0000-0001-9217-3184


ABSTRACT

In this essay, I present a phenomenological exploration of the “urban liminal” in the context of Saul Leiter’s street photography. In gauging the possibilities of dwelling in the urban liminal, this essay brings into dialogue Heidegger’s notion of “wohnen” (as delineated in “Building, Dwelling, Thinking”) and Leiter’s re-presentation of liminal places (and liminality). As transient spatialities, liminal places are not typically considered suitable for dwelling, meaning living or settling. But as neither space nor time is immutable and is always—whether evident or not—in a constant state of flux, it is useful to re-assess and re-imagine from time to time our relationship with place (and time) and, in the process, to reappraise the questions of identity and belongingness. In its investigation of the latencies of liminal places in Leiter’s street photography, this essay poses questions such as: is it possible to dwell (or be at home) in liminalities? How might the visual representation of liminality help deepen our understanding of transitional states and of change? How does Leiter’s stylization of liminality connect with our lived experience of these places? By examining Leiter’s depiction of urban liminality from a phenomenological perspective, this essay aims to show how liminality can be a useful concept for reimagining the relationship between the self and the world.

Keywords: liminal, Saul Leiter, Martin Heidegger, wohnen, dwelling and belonging, phenomenology


“Man lives always on the verge, always on the borderland of a something more.”

(Wheelwright 18)

THE “LIMEN”

The word “liminal” (from Latin “limen” or threshold) implies a transitional phase/space characterized by uncertainty, ambiguity, and often a sense of mystery bordering on the unknown.[1] French ethnographer Arnold van Gennep’s conceptualization of the term in the context of ceremonial rites of passage as observed in certain societies and tribes offers a useful analogy to understand liminality as applied to space/place and to thereby re-imagine our relationship with it.[2] Rites of passage or initiation ceremonies constitute three stages: separation (the dissolution of a former state), transition (the transformational stage or the liminal zone), and incorporation (a state of visible transformation and growth, signalling the formal initiation of the individual into a new state/group). As the quality attendant on an in-between state, liminality encourages openness. The British anthropologist Victor Turner describes liminal spaces as being “betwixt and between” and characterized by “ambiguity and paradox” (97)—attributing “a change in being” (102) to the threshold situation. The inherent in-betweenness of the liminal position involves ambiguity and a blurring of boundaries. However, inhabiting (as opposed to merely occupying) the space of liminality can lead to a heightened and a more nuanced understanding of (our) identity and belongingness (to the world). “In understanding the world,” writes Heidegger, “being-in is always also understood. Understanding of existence as such is always an understanding of world” (Being and Time 146). Since to dwell also implies a transcendental awareness or understanding of place in its specificity, liminal places—as agencies capable of intensifying and deepening that understanding—are always already implicated in dwelling. The liminal connects. Its presence is essential to continuity, to the gathering of places along a continuum. Without an acknowledgement or adequate understanding of it, we risk dissolving space (and time) into an undifferentiated, homogeneous, exclusionary, and ultimately alienating expanse.

LEITER’S NYC AND THE URBAN LIMINAL[3]

As its title suggests, this essay is concerned with the urban liminal and the possibilities of dwelling in and through it. But what exactly is understood by the expression “urban liminal”? To put it simply, the urban liminal may be defined as the in-between places—that are neither here nor there—embedded in the “tangible, built environment” of the city.[4] Zukin situates the concept of liminality in the urban situation; liminality, according to her, “captures the simultaneous advance and decline of economic forms, the sense that as the ground shifts under our feet, taller buildings continue to rise” (5, emphasis mine). Leiter’s New York fits this description in ways more than one—it is a city in flux, at once opening out to the world and retreating in it. But the fact that it maintains itself in the transcendence and that Leiter remains focused on the letting be-ness of the city and its liminal spaces underscore the simple truth of change being constant and essential to the onward flow of life. Even when Leiter executes the defamiliarization of the familiar in his conceptualization of the urban liminal, he seems to be doing so by inviting us (the audience of his photographs) to partake in the multifariousness of the material world.

The city denotes a physical space, a location; its objectivity may as well be received and understood as such. But a city is much more than any specific geographical location. For instance, one may legitimately go on to ask: how is the city shaped by the people who populate its space and the commuters that traverse its streets and liminal pockets? How do such spaces feel to the ones engaging with or experiencing them? What about the numerous transactions, exchanges, and events that unfold every day across the space of the city? Do these events affect our perception of the urban liminal? And then, again, what about the various sensory experiences of the users of the city—the same users, whose behaviours, routines, and everyday mundane transactions (performances) create the perceptual experience of the urban or urbanity (or, the performance of urbanity)? How do we—as the audience and purveyors of Leiter’s photographic portrayal of the space of urbanity—re-construct these spaces in our mind, not just visually but also through the senses of touch, hearing, smell, and taste? For the phenomenological understanding of these spaces will require all these sensory experiences to come together, converge and participate in the process of perception. Merleau-Ponty draws our attention to the sensoriality of perceptual experience:

One sees the hardness and brittleness of glass, and when with a tinkling sound it breaks this sound is conveyed by the visible glass. One sees the springiness of steel and the ductility of red hot steel, the hardness of a plane blade, the softness of shavings. . . . We see the depth, speed, softness and hardness of objects—Cezanne says we even see their odour. (229)

Leiter’s work emphasizes and brings to focus our lived-experience, directing our attention to the nature and essence of things and our everyday encounter with those things. In an attempt to enhance our phenomenological understanding of the city, it makes sense to ask how the audience of Leiter’s photographs (depicting the street life of New York) participate(d)/engage(d) in that very street life through the act of seeing/reading. The city that unfolds across the distinguished and expansive body of Leiter’s photographic art is hardly the outcome of the machinations of the machine age. It is not the postcard NYC with its signature skyline. On the contrary, Leiter’s city—often glimpsed through gaps in the curtain or from under a canopy or as reflected in a puddle after the rains—consists of texts and traces that can be both intimate and distant. For instance, in “Through Boards” (1957) Leiter depicts a street scene, glimpsed presumably from the interior of a boarded-up shop. Like a frozen strip of film, the scene—comprising the prow of a car, a passerby on the sidewalk and two men standing in front of a shop—advances the idea of the street, caught in medias res, as a continually unfolding story, a narrative not only of the city’s becoming and being but also of the individual’s.

If one considers Leiter to be an ethnographer of New York urban street culture he, himself, may be said to occupy a liminal position as one who is both participant and observer, yet never completely either. This convergence of the seer and the seen is further evident in “Paris” (1959), a cafe scene capturing the urban liminal, shot through glass. The slight reflection of the photographer on the glass is barely visible; as both the observer and the observed, he occupies a liminal space. Being a material that is transparent, reflective, and invisible, glass is a useful metaphor for liminality. Armstrong argues that “transparency encourages a simple dualism, or, what is the opposite form of the same thing, the collapse of seer and seen into one another” (11). Glass represents the transitory space where the visible and the invisible converge. This quality of glass shares an obvious resonance with Merleau-Ponty’s concept of embodied consciousness according to which the world comes alive to us (in the act of perception, that is) through a synergy of the visible body and the invisible mind, bound inextricably to each other. Glass features recurrently throughout Leiter’s oeuvre and in works, such as “The Boy”/“The Boy in the Window” (1950), “Graffiti Heads” (1950), “Snow” (1960), “Window” (1957), “Rear Window” (1950), “T” (1950), “Wet Window” (1960), etc. Leiter’s use of glass may be interpreted as a way of articulating one’s relationship with/belongingness to the world. “The Boy,” for example, is shot through a glass window. On the surface of the glass, the seer (the boy) and the seen (reflection of the city’s buildings) converge into layers of superimposed images and reflections. The transparent glass pane of the window functions as a threshold, marking the dissolution of the inside and the outside, the seer and the seen, the self and the other. It is a place of latencies, disclosure, and reflection (both literally as well as metaphorically). The 1960 photograph titled “Snow” is also a case in point. This photograph featuring a man standing on the snow-covered street outside, as only partially seen through the misted glass pane of the window, marks the convergence of the visible and the invisible. Leiter’s expression of the urban liminal is often routed through ephemeral elements of the weather, particularly rain and snow. His visual reflection on liminality, as these photographs seem to suggest, implies an abiding relationship between the subject photographed and the surrounding place/locale. It is perhaps because of this interconnectedness that Leiter’s conceptualization of the liminal does not unsettle or alienate.

As a melting pot of cultures and the seat of the Harlem Renaissance, NYC in the first half of the 20th century could be described with a fair degree of accuracy as a liminal city. A city consists of architecture, fragments of memories, and often failed prototypes of utopian ideations. Leiter’s rendition of New York’s liminality feels intimate—a structure comprising interiority and nearness as opposed to exteriority and distance. His gaze is what David Michael Levin might have described as “the alethetic gaze” that, instead of seeing from a single vantage point, embraces a multitude of perspectives and is inclusionary, participative, empathetic and firmly anchored in the lifeworld or the “flesh” of the world.[5] One might even go so far as to say that what Picasso and the Cubists achieved through the superimposition of forms and perspectives in their paintings, Leiter did through the medium of photography. Leiter’s New York is a palimpsest of traces of the city’s history and performativity—a narrative of its becoming, appearing, and being.

Even to the most casual audience, Saul Leiter’s photographs of the streets of New York are unlikely to come across as objective records of everyday life in the city. Leiter’s purpose—if there is one at all, strictly in the utilitarian sense of the term—is not to record or to document but to offer an experiential account of everyday life as it is lived by real people in a real place. It is noteworthy that Leiter’s experiential narrative, as apparent in and through his photographs of the streets of NYC, appears to privilege a specific mode of seeing that can only be accomplished meaningfully through a combined effort of the senses, not just the visual. A street (or a stretch of a road, or a corridor, or a stairwell, for that matter) is not merely portrayed as such, but as a threshold situation, a transformational zone connecting two discrete and differentiable places/states/spatial realms. In this sense, Leiter’s photographs may be said to embody worlds within a world, inasmuch as they not only contain and preserve within their frames a slice of the world frozen in time but also, in their doing so, assert their status as cultural products caught in the act of a perpetual becoming (in the eyes of the audience). In this latter function the photographs themselves may be said to occupy a liminal space, positioned “betwixt and between” creation and being.

Notably, Leiter appears to challenge the hegemony of the visual and its troubling tendency to write over and suppress the experiences of all the other senses. One way he seems to be doing this is by paying a closer attention to peripheral vision. As Pallasmaa notes: “Unconscious peripheral perception transforms retinal gestalt into bodily experiences. Peripheral vision integrates us with space, focused vision pushes us out of the space, making us mere spectators” (13). There is a conscious and discernible shift of focus to the margins or to things traditionally considered marginal. For instance, Leiter’s photographs of windows—whether taken from the outside or from the inside—privilege a layered vision (as opposed to a single subject dominating the frame), underscoring and reflecting the multifariousness of the material world of things. Leiter’s art puts us back in touch with human rootedness in the world through a thoughtful combination of sensory perceptions. We do not see these photographs merely with our eyes but also (begin to) experience them texturally/haptically (as in the misted-over windows), aurally (as in the silence pervading liminal spaces and in the mute bustle of the streets), olfactorily (as in the anticipation of the nostalgic odour of past occupancies and presences hanging over empty stairwells and alleys), and gustatorily (as in a cafe with its seductive allure of gustatory opulence).

APPROACHING THE URBAN LIMINAL PHENOMENOLOGICALLY

In Logical Investigations, Husserl urges us to go back to the “things in themselves” if we are to glean anything meaningful from our practice of phenomenology—i.e. our attempts to make sense of the nature and the attendant complexities of our lived experience. Wary of the innate ambiguity and arbitrariness of language, Husserl insists that we perform the epoché or bracketing—the suspension of all preconceived notions, ideas, assumptions, and prejudices so that we may turn to the thing-ness of the things we experience, undistracted and unhindered by the weight of our theoretical assumptions and predispositions. To experience something phenomenologically in the Husserlian sense would therefore be to focus on the phenomenon (or thing) under consideration as we experience it. It invites a certain openness to the world around us as we set out to experience it—not just see it, but approach it synergistically from a multitude of perspectives.

With his unwavering focus on the present—the very moment in which the world unfolds and appears to us—Leiter draws our attention to the thing-ness of the material world. His approach, as evident in his portrayal of the street life of NYC, is not an objective account of a specific place or time. In fact, it is quite far from it. While his visual narrative remains resolutely focused on the ordinary and everyday realities of a rapidly growing urban centre, yet it privileges a specific way of apprehending the ordinary that can only be realized meaningfully through embodied experience. Just like in Merleau-Ponty’s philosophy, the human body in Leiter’s photographs—whether visible or not—occupies a central position in the world. It is through the material presence of the(ir) body that his subjects (and by extension, the audience of his photographs) come to be or dwell in the world, and it is again through the(ir) body that the world dwells in them. All formal modes of thinking (and seeing) stand suspended during this process of meaning making since the rigidity of logic and rationality is simply not conducive to the embodied experience of the world.

As it follows, Leiter’s liminal places are particularly amenable to a phenomenological analysis given that they can be experienced more wholly, consummately—albeit, vicariously—in terms of the sensory richness they embody. Leiter’s photographs are therefore best described as re-presentations of sensory impressions in which a thing or a place is not merely what it is, but is also—and more accurately—a palimpsest of impressions converging into a holistic experience of the thing or place photographed.

Leiter’s rendition of liminal places and liminality therefore exhorts us to question our conventional understanding of the essence of place itself. His urban liminal, hardly, if ever at all, comes across as unsettling or terrifying. While one might not “dwell” in a stairwell in the same sense as one would, say, in a house or in a room, yet Leiter humanizes these places to the extent that they do not evoke the dread commonly associated with the disturbingly strange or “unheimlich.” In this context, it is useful to consider Heidegger’s example of the bridge as an analogy for a liminal place: in “Building, Dwelling, Thinking,” Heidegger writes: “The bridge gathers to itself in its own way earth and sky, divinities and mortals” (151). The bridge (joining/gathering the two banks of a river) is a connector; it joins two places bearing distinct identities. It is an in-between place, a threshold. But it is only in the presence of this threshold that the non-liminal emerges and becomes meaningful. Just like Heidegger’s bridge, Leiter’s liminal places also enact a gathering of places.

Phenomenologically speaking, the urban liminal in Leiter’s photographic art is far less about location than it is about a letting be-ness, articulated visually. As Malpas points out, the idea of dwelling seems to be rooted in Heidegger’s idea of authentic existence in Being and Time. According to Malpas, dwelling in Heidegger’s philosophy ensues from the idea of “authentic existence” and that to live an authentic life may be considered equivalent to dwelling.[6] Besides authenticity, as Malpas makes it clear, Heidegger’s idea of dwelling seems to be closely linked to that of identity and belonging. Given that by authenticity Heidegger actually points towards “an openneness to the happening of place” (Malpas 14), to belong to any specific place would mean to identify with it and be completely attuned to it. To belong to a place, to dwell in it actively (as opposed to merely occupying it) in the Heideggerian sense would automatically imply that we are at home and at peace in it and that it “opens us to the world and the world to us” (15). Leiter’s rendition of the urban liminal, reminiscent of the Japanese ukiyo-e or “pictures of the floating world,” frees the everyday into its own being.[7] In his portrayal of the everyday life of urban NYC, Leiter seems to draw our attention towards the mystery that lies at the heart of the mundane. Works such as the 1950 series “From the E,” “Graffiti Heads” (1950), “Shirt” (1948), etc., are cases in point. These works capture everyday life in medias res—often defying compositional conventions. “Shirt,” for instance, is a deceptively simple yet enigmatic image of a neatly-folded shirt on display outside what appears to be a glass-fronted shop doorway. The image calls our attention to the tacit interaction between the narrative of the place and that of the body (as represented by the shirt). In this case, the shirt occupies a liminal position, linking the biological body to the social being. Furthermore, the meander motif on the floor, placed at the threshold between the public and the private, seems to suggest the eternal flow of things.[8]

According to Leiter, the real world is less about what can be seen than what lies hidden—the unseen, the untold, the unknowable.[9] The experience of the urban liminal in Leiter’s portrayal of the everyday often evokes the notion of Japanese space (or, ma).[10] The liberal use of negative spaces in works such as “Through the Boards,” “Canopy,” etc., conveys the idea of “meaningful” absence, encapsulating possibilities of disclosure—a sort of openness to and opening of the world. Leiter’s photographs can therefore be seen as a visual representation of Heidegger’s idea of world-disclosure that seems to occur at two levels: first, the disclosure of a world in which we find ourselves, that which is always and already interpreted (the mundane everyday world); and second, the disclosure of hitherto unknown or hidden horizons of meaning. It is to this latter sense of disclosure of the world that Leiter’s images are most unreservedly attuned. They invite viewers to perceive the city not as an objective or static space but as a dynamic, lived experience. Concomitantly, by examining Leiter’s work through a phenomenological lens, this essay explores how his photographic art captures the essence of dwelling in an urban context, where individuals navigate the city and its liminal spaces. This connection underscores the idea that even in the bustling, ever-changing urban environment, there is a possibility for a sense of “wohnen” or dwelling—a feeling of being at home in the world. Instead of evoking discomfort or dread, commonly associated with liminal spaces, Leiter’s liminal city embodies the idea of infinity in its openness. It is precisely within these liminal spaces (of the city) that this attunement to the world comes across as most perceptible. Leiter’s work, therefore, provides a visual narrative that complements and enriches the philosophical exploration of Heidegger’s “wohnen.”

CONCLUSION

In order to arrive at any conclusion regarding the possibility of dwelling in liminality or in liminal places, we must first confront and address the problems posed by the essentially deterministic and exclusionary logic of place. For dwelling to occur in liminal places, the subject must first be at home/in peace with her being and second, be aware of and in peace with her embedded-ness in/belongingness to the world. Therefore, it may be said that if and when liminality is perceived/experienced as something that obfuscates or unsettles our relationship with ourselves and the world, dwelling cannot occur or be realized. For dwelling to occur the “limen” must, of necessity, preserve the being and receive it as such. On the other hand, the self, in order to be at home in itself must be aware of itself, for awareness of the self about itself implies room for reflection and disclosure. The self opens out to the world in Leiter’s liminal zones. The “I” extends itself to the other—cultivating and preserving, at the same time, its own integrity and sapience.


Satarupa Sinha Roy is Assistant Professor at the Department of English in Dewan Abdul Gani College, India. Satarupa has received her doctoral degree in English from the University of Calcutta in 2015. She has published essays and presented papers on multidisciplinary topics (e.g., travel writing, visual cultures, philosophical interpretations of literature, education, etc.) in reputed academic journals both in India and abroad. Her current research interests include phenomenology and narrative inquiry, the intersection of travel writing and the visual arts (particularly, painting and photography) and the short story.

satarupas@gmail.com



Works Cited

Armstrong, Isobel. Victorian Glassworlds: Glass Culture and the Imagination 1830–1880. Oxford UP, 2008.

Harvey, David. Social Justice and the City. Edward Arnold, 1979.

Heidegger, Martin. Being and Time. Translated by John Macquarrie and Edward Robinson, Harper & Row, 1962.

Heidegger, Martin. “Building, Dwelling, Thinking.” Poetry, Language, Thought, edited and translated by Albert Hofstadter, Harper & Row, 1971, pp. 145–61.

Husserl, Edmund. Logical Investigations. Translated by J. N. Findlay, Routledge, 1970.

In No Great Hurry: 13 Lessons in Life with Saul Leiter. Directed by Tomas Leach, Zeitgeist Films, 2013.

Kappraff, Jay, Ljiljana Radović, and Slavik Jablan. “Meanders, Knots, Labyrinths and Mazes.” Journal of Knot Theory and Its Ramifications, vol. 25, no. 9, 2016, pp. 1–22. https://doi.org/10.1142/S0218216516410091

Malpas, Jeff. Rethinking Dwelling: Heidegger, Place, Architecture. Bloomsbury, 2021. https://doi.org/10.5040/9781350172944

Merleau-Ponty, Maurice. The Phenomenology of Perception. Routledge, 1962.

Pallasmaa, Juhani. The Eyes of the Skin: Architecture and the Senses. John Wiley, 2005.

“‘Saul Leiter, the New York Nabi’ on L’Oeil de la Photographie.” Saul Leiter Foundation, https://www.saulleiterfoundation.org/latest-news/loeil-de-la-photographie, accessed 27 Sept. 2023.

Turner, Victor. The Forest of Symbols: Aspects of Ndembu Rituals. Cornell UP, 1967.

van Gennep, Arnold. Rites of Passage. Chicago UP, 1960.

Vermare, Pauline. “Saul Leiter: The New York Nabi.” Blind Magazine, 3 July 2023, https://www.blind-magazine.com/news/saul-leiter-the-new-york-nabi/, accessed 30 Jan. 2024.

Wheelwright, Philip Ellis. The Burning Fountain: A Study in the Language of Symbolism. Indiana UP, 1968.

Zukin, Sharon. Landscapes of Power: From Detroit to Disney World. U of California P, 1991. https://doi.org/10.1525/9780520913899


Footnotes

  1. While the concept of liminality may, with equal salience, be applied to both space and time, this essay focuses only on liminal places or the urban liminal in the context of Saul Leiter’s street photography.
  2. Arnold van Gennep’s pioneering study on the individual’s transition in society through ceremonial rites (the rites of passage), Les Rites de Passage, was first published in French in 1909 and was subsequently translated into English in 1960.
  3. Saul Leiter (1923–2013) was born in Pittsburgh and became widely known as a fashion photographer in New York. Leiter was originally trained to be a painter so his photographs bear palpable traces of painterly techniques. Leiter photographed the streets of New York extensively in the 1940s and 50s, and even afterwards, in a style that may be described as “slices of life.” Working in an era when fine art photography was decidedly monochrome, Leiter used colour blocks in his photographic compositions in a striking way, often calling to mind the art of contemporary painters, particularly Piet Mondrian and Mark Rothko. Leiter’s deeply humane art is rooted in and foregrounds the everyday alike, in its brilliant immanence and impermanence.
  4. Harvey defines the city as “a tangible built environment—an environment which is a social product” (96). His emphasis on the city as a tangible social construct seems to have a definitive bearing on the way(s) dwelling is actually practiced/realized within its mutable (and continually mutating) space.
  5. Levin differentiates between the “assertoric gaze” and the “alethetic gaze” in his book, The Opening of Vision: Nihilism and the Postmodern Situation. While the assertoric gaze is narrow, rigid, exclusionary, and dogmatic, the alethetic gaze is essentially pluralistic, tolerant, and accommodates a wide range of perspectives (qtd. in Pallasmaa 36).
  6. See chapter “Rethinking Dwelling” in Malpas.
  7. The word ukiyo embodies the Buddhist idea of the transitory nature of life. Unlike the Pure Land (heaven), “ukiyo” (this world) is transient and fleeting. This quality (the flowing, fleeting nature of the world), characterized by a certain uncertainty or unknowability engulfing the material world of things (a sense of mystery) is evident in Leiter’s work. At around the end of the 19th century (the Meiji Restoration), a fascination for Japanese aesthetics (Japonisme) began to be felt across Europe and the United States of America. Japanese Ukiyo-e prints by Hokusai, Hiroshige, and Utamaro made a great impact on the artistic imagination of European and American painters in terms of technique, composition, and use of color. Leiter was greatly influenced by the French artist Pierre Bonnard (also nicknamed the Japanese Nabi) who incorporated elements from the ukiyo-e aesthetic in his art. Influences of Japanese art—particularly, ukiyo-e—are also evident in Leiter’s composition. Pauline Vermare, the curator of Leiter’s first show in Japan, quotes Jun’ichiro Tanzaiki to underline the influence of Japanese art on Leiter’s work: “‘We love things that bear the marks of grime, soot and weather, and we love the colours and the sheen that call to mind the past that made them.’” See https://www.saulleiterfoundation.org/latest-news/loeil-de-la-photographie I am indebted to Vermare’s article (the edited version of an essay published earlier on the occasion of Leiter’s first exhibition in Japan) titled “Saul Leiter, the New York Nabi” (Blind Magazine, 2023), which is a nuanced account of the Japanese influences running through Leiter’s art.
  8. The meander motif is also known as the Greek key or Greek fret. In ancient Greece, the meander motif often suggested the eternal flow of things. For more on this, see Kappraff, Radović and Jablan.
  9. See Tomas Leach’s documentary film In No Great Hurry: 13 Lessons in Life with Saul Leiter (2013).
  10. See Vermare.

COPE

© by the author, licensee University of Lodz – Lodz University Press, Lodz, Poland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license CC-BY-NC-ND 4.0 (https://creativecommons.org/licenses/by-nc-nd/4.0/)