Why this state of things?
Even though political motivations have been at the core of the erosion of truth in our societies, the post-truth era is not simply a by-product of populism (Salgado 2018). It is impossible to attribute these developments to one single reason. Instead, a number of factors have contributed to the decline of the importance of the truth and to an increased emphasis on duelling fact perceptions driven by emotions and misinformation. Lewandowsky, Ecker, and Cook (2017) see the post-truth era as a result of societal mega-trends, such as a decline in social capital, growing economic inequality, increased polarisation, declining trust in science, and an increasingly fractionated media landscape.
This is an era in which emotions seem increasingly to matter more than facts. Objective facts are often less influential in shaping opinions than appeals to emotions and beliefs (e.g. in different types of populist discourse, in which the resort to emotions, such as the exploitation of fear and resentment, always outweighs reasoned arguments). In this sense, we could say that post-truth politics is more a symptom of the current social and political status of the truth than it is their cause (Salgado 2018).
The current changes to the status of the truth are partly explained by the relativism of the post-modern age that emerged as a response to the unified, definite meanings and universal truths of the modern age (see, e.g. Foucault 11969J 2002 or Lyotard  1991). Postmodernism questions these ideas and values of modernism and proposes a relativism of the truth (and facts) that lies deep in intersubjectivity and in upholding diversity as an aim in itself. ‘The difference between modernity and post-modernity lies precisely in the proposal of an ontology of reality versus a construction of reality', that is, if reality pre-exists to be discovered or if it is instead constructed through subjective discourse and interpretation’ (Salgado 2018, 321).
In the post-modern world, reality’ does not pre-exist its interpretation; reality’ is the negotiation of meaning in each individual that results from the interplay of different factors, including identity, personal experience and beliefs, and type of media exposure and use. Reality is thus developed in relation to a specific context and to individual features and assessments. Consequently; not only’ moral norms (good and bad, right and wrong, etc.) but also what is considered truth and untruth depends on the context and is subject to diverse, often competing interpretations and meanings. This ultimately means that there is no absolute or definite truth and that knowledge and values are constructed through discourse and experience (see, e.g. Rorty’ 1991).
Such an ethos spurs and gives rise to the co-existence of a wide range of (often contradictory) interpretations of reality and values, which ultimately make the entire search for the truth a meaningless process as there are several truths and not just one truth. In this respect, postmodernism perfectly accounts for the post-truth mindset. This approach to reality and knowledge affects the value of the truth and the perception of facts and also has a decisive impact on democratic politics. There have always been different ideological and partisan positions in democratic politics, but they would proceed from a shared basis in fact. A society in which there is no agreed body of facts renders democratic decision-making virtually impossible.
These are changes that are still unfolding in time, and, in some cases, elements of modernity subsist in post-modernity (see, e.g. Giddens 1990), but there is nevertheless a noticeable change in contemporary Western societies that adheres to growing levels of relativism in different aspects of life, including politics. We are now very likely to find cases in which knowledge and belief and truth and falsehood are completely blurred.
Before the so-called post-truth era, there was the belief that the truth was out there to be found and that there were mechanisms based on factual objectivity (e.g. scientific method, journalistic procedures) to assist those interested in that pursuit. Now, underpinned by technological advancements, the notions of relativism and subjectivity have been expanded to all domains, including facts and information. The growing relativism of the truth (and facts) in our societies could thus lead to situations in which there is no common understanding of basic facts as their meaning results from the negotiable expression of identities, experiences, opinions, and preferences. This shift in paradigm and the ensuing consequences for information could lead to information ecosystems in which diversity (diversity here does not necessarily mean plurality) is valued and enhanced, but quality does not need to be necessarily part of the equation, particularly if it is achieved at the expense of diversity.
Implications are also noted for moral and ethics standards because they are interpreted according to context and thus become relative to specific points of view. There is much more flexibility in the meaning that is attributed to virtually everything, which is also what Bauman (2007) refers to as ‘liquid’ times. This applies to discourses about scientific facts as well (e.g. global warming and climate change, vaccination) and to politics, which may pose important ethical dilemmas, particularly when it impacts not only on political discourses but also on ways of governing and political action in general.
Much of what is considered post-truth politics is thus explained by the post-modern cultural ethos, but it is also related to known features of politics and political propaganda that have been amplified by technology', in particular social media (Salgado 2018). The internet and the digital culture have caused and intensification and amplification of some of the main features of postmodernism, and the pace of change has accelerated significantly, which has led some scholars to suggest new terms to designate the era in which we currently live in (e.g. Nealon’s  notion of post-post-modernism). In politics, several of post-truth’s most notable features are actually old attributes. There are important political precedents behind the post-truth era: lies, rumours, deceits, and manipulation tactics have been used to shape public opinion throughout history (Salgado 2005).
There is even a long-standing debate on whether deception is good or bad for politics. Particularly for those sceptical of democracy, deception is seen as an inherent part of politics; it is not only fully justifiable but also necessary (Robinson et al. 2018). But even the most enthusiastic democrat recognises, once in a while, the necessity of governments and political leaders lying and using deception in specific circumstances. Election campaigns (and other situations of political competition) are moments in democracy that are commonly noted for stretching the boundaries of truth and facts as political candidates usually go the extra mile to convince voters, but crises, in foreign affairs or domestic politics, are deemed to justify the use of deception by governments.
The work of spin doctors and other political communication professionals is specifically related to conveying favourable interpretations of events to the media and the public (e.g. Louw 2010; Salgado 2014). Shaping the information environment and preparing the climate of opinion for the announcement of decisions often mean resorting to tactics that are not transparent and based on authenticity, or even to deception. The use of these tactics entails the selection and framing of information that is presented in ways that are meant to be, first and foremost, convincing and appealing. Notwithstanding the excesses that tend to occur due to loose interpretations of what the limits should be, such strategies are considered part of the normal functioning of democracy in todays societies. Robinson et al. (2018) refer to ‘organised political communication’ and to the use of deception by lying, omission, distortion, or misdirection.
While politicians produce strategically advantageous interpretations of reality, citizens’ perceptions are also shaped by their choice of medium (Logan 2004) and political preferences (e.g. Bartels 2002; Jerit and Barabas 2012; Hochschild and Einstein 2015). Biased political communication with the purpose of promoting a specific position — that is to say, hypes and propaganda — acts upon the individuals’ pre-existent political preferences (e.g. political interest and sophistication, ideology, partisan attachment) and psychological mechanisms that are known to affect perceptions and attitudes. It is, for example, the case of selective attention, prior-belief bias, affective bias, and motivated reasoning processes. By choosing content that confirms their beliefs while avoiding and denying what is divergent and conflicting, individuals tend to expose themselves to, process, and evaluate information in a biased manner. Selective attention is a well-known mechanism in cognitive psychology that basically explains that because individuals cannot focus on everything all the time, they focus on what matters the most to them (e.g. Graf and Aday 2008). Motivated reasoning basically means that people’s goals and predispositions influence how they interpret information (Kunda 1990; Petersen et al. 2013; Stanley et al. 2020). Perceptual biases are shortcuts that individuals use to make sense of the world. Because they are shortcuts, they only provide a partial understanding and may thus be misleading. For example, politically motivated reasoning makes individuals view politics through the narrow lenses of ideology and partisanship. In a polarised context (among others), people are likely to see their choices as right and good and to evaluate the choices that are different from theirs as wrong and bad. On the demand side, these shortcuts influence information exposure when individuals seek information that supports their beliefs and preference, while on the supply side, resources are devoted to shaping the information environment.