Modernist writing centres on the experience of man living in the world around him. When this world becomes autonomous of man, or becomes a world that man can no longer position himself within, an existential crisis of identity is bound to ensue. This is reflected in the work of Charles Baudelaire, whose 'psychology is insoluble on the biographical plane, because there is no discernible centre of coordination, no unification'  . The problem of identity in the modern world is a key theme within Paris Spleen, and this is not surprising when we consider the fact that the Paris in which Baudelaire died was very different to the Paris in which he was born. When Georges Haussmann became Prefect of the Seine in 1853, he was appointed the task of modernising and transforming Paris from an unrefined yet 'picturesque mediæval city â€¦ which â€¦ harboured exultant memories of the days of the revolutions'  , to 'the model of European town planning'  . Haussmann was ruthless and scrupulous in his efforts to make Paris a 'the envy of all capital cities'  ; he strove to eradicate the presence of the lower classes within Paris, constructing barracks throughout the city to limit their voice of protest, and remodelling the city's identity to create 'an immense market place and workshop, an arena for the ambitious and a rendezvous for the pleasure seeker'  . This shift in focus towards a more capitalist, modernised society came at the expense of the lower class citizens, who were driven out of the city to facilitate such expansion; 'Indeed, the fundamental effects on the life of Paris were, for Haussmann, almost side issues.' 
Haussmann's modernisation of Paris is a contentious issue in Paris Spleen, and Baudelaire laments these changes within his work. Baudelaire was raised in a bourgeois family, yet strove to disassociate himself from such a position within the social hierarchy, befriending prominent socialist Pierre-Joseph Proudhon and choosing to live a hedonistic bohemian lifestyle. For Baudelaire, the bourgeois and the poor represent two different sets of values. The bourgeois (who encompass not only the middle-class and the aristocracy, but also the established institutions such as the government and the Church) represent Haussmann's modern-day Paris. In his eyes, they do not embody the ideals under which the French republic was founded ('Liberté, Égalité, Fraternité), but instead represent arrogance, self-righteousness, self-interest and narcissism. This is seen in 'The Mirror', where an 'appalling-looking man'  justifies his vanity by stating that 'according to the immortal principles of '89 â€¦ I have the right to look at myself in the glass'  . The protagonist mourns the fact that such egotism can feasibly be constitutionally justified, and draws a binary opposition between the concepts of 'the point of view of the law'  and common sense, thus indicating his detachment from modern French society and the government that controls it.
On the other hand, the poor represent pre-modernity Paris in Baudelaire's work. They are cast in his works to embody the founding principles of the French republic, and as their presence within the city slowly dwindles, so does any hope for the survival of these values. This is a source of great humiliation for the bourgeois protagonist in 'The Eyes of the Poor'. The protagonist and his partner are frequenting a 'dazzling' 'new café forming the corner of a new boulevard still littered with rubbish', when they spot 'a worthy man of about forty' and his children, who 'were in rags'; one of whom was 'too weak to walk'. The protagonist feels ashamed that in a society founded under the premise of brotherhood and equality, he should be in such a lavish, gluttonous surrounding, drinking from 'glasses and decanters, too big for our thirst', whilst mere metres away from him lies complete poverty. What is perhaps more astounding is the remarkably accepting view that the poor man and his children adopt towards the decadent new construct, as they 'stared fixedly at the new café with admiration'. This is then countered by the bigoted attitude of the protagonist's partner, who states '"Those people are insufferable with their great saucer eyes. Can't you tell the proprietor to send them away?"'. This provokes feelings of resentment in the narrator towards the new Parisian society in which he lives, and he feels as if he has no one to which he can relate; he is torn between his bourgeois upbringing and his lower-class sympathies. Even love cannot survive under such conditions, as the values by which he leads his life have been forgotten by all those around him. This is exemplified where the protagonist declares 'so you see how difficult it is to understand one another, my dear angel, how incommunicable thought is, even between two people in love'  .
With the death of republican principles comes an increased sense of social isolation and resentment on behalf of the protagonist. He becomes a reclusive cynic, stating that philanthropy is merely 'the brotherhood of prostitution'  . Added venom is inferred through the use of the word 'brotherhood', which means 'fraternité' in French. Such cynicism drives him to discover new means through which he can tolerate living in modernised Paris, and this escapism manifests itself through his pursuit of intoxication. In 'The Double Room' the protagonist describes how the only way that he can escape from 'this narrow world'  is through visiting 'A room that is like a dream, a truly spiritual room'  . How does he find this room? Through 'the vial of opium'  . The room is described as 'bluish shot with rose'  , and one could argue that this refers to the colours of the red, white and blue Tricolore merging to form a hazy and distant recollection of the former glory of the French republic. This interpretation is reinforced through the appearance of 'the Idol, the sovereign queen of my dreams'  , who the protagonist claims to recognise. Could this serve to represent Marianne, the emblematic female embodiment of liberty and reason within the French republic? This blissful imagery is then destroyed through the receding of the opium. 'Time', which is representative of modernised France, is consequently restored, bringing with it 'his brutal tyranny' and 'the entire retinue of Memories, Regrets, Spasms, Fears, Agonies, Nightmares, Nerves and Rages.'  Baudelaire requires 'a dialogue with the city that simultaneously makes possible to escape from it'  . In order to manageably exist in modernised Paris, Baudelaire's protagonist is forced to flirt with it in small doses, and means of escapism such as intoxication help to facilitate this.
Latin American modernist literature grew in at a different pace to the way in which it did in Europe. In Latin America, the division between the literate, educated bourgeois and the illiterate, uneducated poor was even more polarised than in Europe, and this meant that the bourgeois society that is so often undermined in Baudelaire's work was the only real audience that a Latin American modernist writer could expect. This was problematic for Julio Cortázar, who staunchly opposed to the governmental regime of Juan Perón in his home country of Argentina. As a result of this opposition, he exiled himself to Paris in 1951, where he lived for the rest of his life, and this set a premise for some of the themes of identity and social isolation within his work that I shall now discuss. I would argue that perhaps the most obvious depiction of social isolation within Cortázar's work would be in 'House Taken Over'. The narrative follows a brother and sister, who live together in Buenos Aires. The protagonist is clearly well-educated, as he owns a 'collection of French literature'  ; a euro-centric interest which denotes linguistic ability and a cultured worldly outlook. They live a life of relative monotony, but they 'never bothered anyone'  . The unknown, mysterious force that compels them to discard half of their house, and finally drives them from it, leaving behind all of their money and possessions is never specified. However, I would argue that this mysterious force is designed to represent the regime of Juan Perón, whose politics drove Cortázar away from Buenos Aries and forced him into self-imposed exile in Paris; 'Cortázar had felt ill at ease with Argentina's political and social trends in the late forties, and its cultural life seemed to him to be ossified and restrictive'  . The reference to French literature could obviously relate to Cortázar, as he was born in Belgium (yet moved back to his parent's native Argentina when he was four) and was fluent in French. In addition, the violent yet non-confrontational manner in which the siblings are convinced to leave reflects the manner in which a repressive governmental regime may force one to want to exile oneself from that particular society. This is exasperated due to the threat of violence denoted by the mildly aggressive noises they hear, such as a 'chair being knocked over onto the carpet'  . This could indicate that the protagonist is an outsider in relation to his wider social environment, as he has been forced from the comfort and security of his own home, which 'kept the memories of great-grandparents, our paternal grandfather, our parents and the whole of childhood'  . In addition, the key to the front door that is thrown in the sewer at the end of the story is indicative of Cortázar's decision to permanently exile himself from Argentina, as although he returned to visit the country, he never came back to live there. Further weight is added to this argument due to the fact that one of the bedrooms within the house is described as 'faced towards Rodríguez Peña'  . Nicolás Rodríguez Peña was an Argentine politician whose soap factory was used as a head quarters for conspirators during the early nineteenth century revolution against Spanish rule in Argentina. By incorporating such political iconography within the text, Cortázar adds a reactionary anti-establishment undertone to his narrative, and this helps to reinforce the characterisation of the protagonist as an outsider within his wider social environment.
However, this theory is merely interpretive, and we cannot possibly know the true identity of the mysterious intruder; 'When its door is finally slammed - meaning is entirely entrusted to the reception of the reader'  . This is an important concept, as the idea of the outsider is now turned towards the reader, who having been brought into the world of the text through the need for interpretation, no longer assumes the role of outsider himself, but becomes a contributing part within the text. This leads me nicely onto my next topic of discussion; the way in which Cortázar and Baudelaire's innovative and avant-garde approaches towards style and form evoke the idea of social isolation. Their contemptuous reaction to realist literary conventions led each author to strive to find a new, original, non-realist approach to literature. This literary experimentation led both authors to place an emphasis on 'making fiction â€¦ more dynamic, protean, and variable'  , and by doing this, they 'pursue that "incessantly varying spirit" of "life itself", forcing 'the inner life of the mind â€¦ onto fiction's public page'  .
Baudelaire states his intent to develop this style in his letter 'To Arsene Houssaye', in which he asks
Which one of us, in his moments of ambition, has not dreamed of the miracle of a poetic prose, musical, without rhythm and without rhyme, supple enough and rugged enough to adapt itself to the lyrical impulses of the soul, the undulations of reverie, the jibes of conscience? 
Baudelaire wished to create a 'poetic prose' that would allow individual readers the scope to form new and original interpretations, each different and relative to their own thoughts and characteristics. This stylistic approach came as a result of the social isolation he experienced whilst living in modernised Paris; 'It was, above all, out of my exploration of huge cities, out of the medley of their innumerable interrelations, that this haunting ideal was born'  . Baudelaire describes realist art as 'artistic abominations'  , and states that 'Definite, positive art is blasphemy compared to dream and the unanalyzed impression. Here all is bathed in harmony's own adequate and delicious obscurity'  . Through inducing this sense of 'delicious obscurity' within his work, and leaving room for individual interpretation, Baudelaire forges an authorial identity of his own, and it is this identity that immortalises him in the annals of literary history. Jones provides us with a nice summary of this effect where he writes
the psychological element â€¦ had contributed more than any other to placing the poems hors concourse. The task is to appreciate that element, not in the mind of the man writing letters or entering notes in his diary, but as a living ingredient in his poems. 
Due to the largely bourgeois readership of Latin American modernist writers, authors such as Cortázar had to be a little more tactful in their criticisms of aspects of society that may involve the bourgeois, such as politics or wealth distribution. Consequently,
Boom' writers such as Cortázar relied heavily upon 'a heightened sense of the mystery and ambiguity of things andâ€¦ a greater reliance on fantasy and the creative imagination. In addition, new areas of reality, both social and individual, came to be explored. To express this shifting vision, new experimental narrative strategies had to be developed 
This focus upon fantasy and the creative imagination was explained by Cortázar himself, as we see where he says that 'almost all of the stories I have written belong to the genre called fantastic, for lack of a better word, and are opposed to that false realism that consists of believing that everything can be described and explained'  . As with Baudelaire, we see evidence of the writer refuting literary realism, and instead focusing upon
deliberate abandonment of linear, chronological narrative, of conventional character-presentation and of obtrusive authorial authority, a much more sophisticated viewâ€¦ of the role of language in fiction, and as a general consequence a greater tendency toward "writerly" rather than reader-friendly fiction. 
A good example of this would be 'Axolotl'. From the very beginning of the story, narrative perspective is playfully handled, and this experimentation with narrative perspective is used to signify a pursuit for identity within the protagonist's wider social environment. We are told that 'there was a time when I thought a great deal about the axolotls â€¦ Now I am an axolotl'  . This is typical of Cortázar, who provides us with 'a detached observer â€¦ who makes no attempt at interpreting reality for us'  , and this renders his work 'easy to read but very difficult to understand'  . This relationship between the protagonist and the axolotl centres on the fact that the axolotl represents 'a now imprisoned, but once non-colonized, autonomous, "Aztec" being, space and identity'  , to which the narrator, who is presumably a Latin-American living in Paris, can relate. The axolotl is associated with 'the "roots" of Latin America, with a kind of origin'  , and the narrator relates to the creature, proclaiming that 'something infinitely lost and distant kept pulling us together'  . In short, 'the pre-colonial subject [axolotl] represents the lost authentic self â€¦ of the contemporary, colonized person [narrator]'  . The reader is made fully aware of the extent to which the narrator longs to be associated with the axolotl when further experimentation with narrative form ensues. On describing the condition of their tank, he says that 'the axolotls huddled on the wretched narrow (only I can know how narrow and wretched) floor of moss and stone'  . It is the bracketed change in narrative perspective that is particularly interesting, as one would expect the axolotls themselves to have the most comprehensive understanding of their tank, yet the narrator claims the he understands better than anyone. This provides the reader with an 'interfusion of â€¦ material and spiritual forces, the intimate unity of the modern self and the modern environment[as seen through the eyes of the axolotl]'  , and gives an indication of the extent to which the narrator really does believe that he can identify with these creatures, which represent his past and his origins. By doing this, and by manipulating narrative form, the reader is given a more complete emotional understanding of the feeling of alienation that the protagonist is going through. Cortázar's attempts to create a 'literature beyond all naÃ¯ve realism'  renders his work more emotive, more affecting, and ironically far more real.
In conclusion, within both Baudelaire and Cortázar's work there is an innate desire for an identity that relates to their wider social environment. For Baudelaire, it is pre-modernity Paris that he most strives to relate to, yet this is not possible due to the complete renovation of the city that occurred in his lifetime. Feelings of acceptance and comfort can only be derived from artificial forms of escapism, such as alcohol and drugs, and whilst they provide some temporary respite, they are transient, and cannot fully satiate his desire for social acceptance. The only way in which Baudelaire can form an identity is as a writer, and although this may not have helped him to deal with his reservations regarding social identity, it certainly helped him to form a style which came to define him, and his works are now as much a part of the city's identity as any Haussmannian structure. Paris is now associated with Baudelaire; his obscure yet voluptuous snapshots into Parisian life provoke questioning that draws us into the text and allows us to form different readings of it, each individual and reflecting the character of the reader. Cortázar does not have the hedonistic flair of Baudelaire and as such laments the loss of his position within Argentinean society in a far more accepting less overt manner. However, similarly to Baudelaire the lack of aesthetic detail within his short stories forces us to question and to create our own readings of them, and this draws the reader into the world of the text. We are outsiders no longer.