We have to start from where we are.
Normally, when we speak of solidarity, we mean “human solidarity” or “solidarity between humans”, ideally all humans, rich or poor, black or white, male or female, or anything in between or intersecting these, in short, despite all differences. There’s no doubt that this kind of solidarity is absolutely desirable and crucial, especially in critical times like ours, when the gap between rich and poor humans is widening, racism and sexism persist and new threats like human-induced climate change, biotechnology and genetic engineering are putting the survival of an increasing number of species, including the human, into question. It is hard to see how the kind of solidarity called for under these circumstances could not, as Richard Rorty wrote, rely on the idea that “there is something within each of us – our essential humanity – which resonates to the presence of this same thing [i.e. human solidarity] in other human beings”.
Rorty’s aim was to get rid of this (human or humanist) essentialism without jettisoning the principle of solidarity. As a liberal pragmatist, he insisted on the “contingency” of human identity and rejected the need for notions like “essence”, “nature” or “foundation”. However, if “what counts as being a decent human being is relative to historical circumstance, a matter of transient consensus about what attitudes are normal and what practices are just or unjust … [w]hat can there be except human solidarity, our recognition of one another’s common humanity?” In other words, how can there be solidarity without a rather abstract and remote notion of “our common humanity” – which has never stopped “us” from insisting on the finer differences, the more or less humanness of “others”, women, blacks, indigenous, trans … “people”. Yet it’s arguably not so much that a sense of humanity cannot be achieved, it’s rather that it just cannot be based on any essential commonality. It can only be achieved “pragmatically” and “locally”, Rorty would argue: “our sense of solidarity is strongest when those with whom solidarity is expressed are thought of as ‘one of us’, where ‘us’ means something smaller and more local than the human race”. Does this not sanction the worst sort of parochialism, a defence of the status quo, and any form of “ethnocentrism”? Not necessarily. It doesn’t do away with the desire and the necessity of solidarity, it only displaces it from an absolute and abstract moral obligation into the terrain of pragmatic politics and confronts it with its own historical contingency, i.e. its embeddedness in the vocabularies and traditions of “the secularized democratic societies of the West”. Rorty’s main pragmatic claim regarding solidarity is that it is “made rather than found, produced in the course of history rather than recognized as an ahistorical fact”. This is an important insight, especially at a time when universalizing concepts like the “Anthropocene” threaten to erase historical, economic and social differences like unevenly distributed rights, responsibilities and benefits and sufferings. As far as the threat of extinction at the level of species is concerned, we are, it is claimed, all concerned equally. This is where a call for human solidarity begins to sound and feel like a cynical denial of historical and political contingency and difference.
Solidarity when facing such a common threat that nevertheless calls for differentiation as to cause and effect – who’s responsible and who’s most concerned? – can only be achieved without a pre-existing notion of “truth”, “reason” or “nature”. It can only be achieved through (re)negotiation not by “recognizing” something that supposedly “pre-exists” in the form of an “essence” (like “human nature” for example). It cannot take the form of a “neutral” and timeless (moral) obligation. Hence Rorty’s standpoint:
I want to distinguish human solidarity as the identification with “humanity as such” and as the self-doubt which has gradually, over the last few centuries, been inculcated into inhabitants of the democratic states – doubt about their own sensitivity to the pain and humiliation of others, doubt that the present institutional arrangements are adequate to deal with this pain and humiliation, curiosity about possible alternatives.
So let’s take Rorty at his word, especially since he proposes what one might call a (proto)posthumanist move as far as the extension of solidarity is concerned, when he writes that a pragmatic notion of solidarity not relying on universalist, foundational and essentialist ideas “is incompatible with the idea that there is a ‘natural’ cut in the spectrum of similarities and differences which spans the difference between you and a dog, or you and one of Asimov’s robots – a cut which marks the end of the rational beings and the beginning of the nonrational ones, the end of moral obligation and the beginning of benevolence”. This is strikingly similar to what Donna Haraway proposed in her “Manifesto for Cyborgs” in 1985 – certainly one of the foundational texts of critical posthumanism. In a sense, Rorty here even anticipates Haraway’s own subsequent move towards (or at least shift of emphasis on) companion species more generally.
If solidarity should not or cannot presuppose a shared “human nature” on which a universally distributed “rational being” can rely to found a moral obligation towards others then new forms of inclusion (and exclusion as well, of course) not only become visible but even necessary as the remit of moral obligation changes and widens. This is, in my view, where Timothy Morton’s Humankind: Solidarity with Nonhuman People (2017) comes in. Morton starts by (re)thinking a (communist) politics for our time as planetary (and not just “international”) in scope, a planetary politics attuned to the fact of “living in a biosphere” – which he calls “the symbiotic real”. This planetary biosphere constitutes the “phenomenology” of shared biological and evolutionary co-existence – without any doubt an openly “biocentric” approach threatening to exclude “Asimov’s robots”, as Rorty would put it. “The right word to describe this reliance between discrete yet deeply interrelated beings”, Morton writes, is “solidarity”, without which, “the tattered incompletion of the symbiotic real at every scale … [it, i.e. solidarity] would have no meaning”. Solidarity only works, he claims, “when it is thought at this scale”. It is the precondition for what he calls “humankind” (as opposed to humanity, playing on the generic meaning as well as on its “kindness”) understood as general ecological awareness.
The kind of solidarity (with nonhuman people) Morton has in mind starts with acknowledging and overcoming what he calls the “Severing”: in Lacanian psychoanalytic terms, “a traumatic fissure between … reality (the human correlated world) and the real (ecological symbiosis of human and nonhuman parts of the biosphere)”, a foreclosure that has been occurring since the Neolithic when humans turned to agriculture and settlement. To work through this foreclosure one has to recognize that solidarity is in fact the “default affective environment of the top layers of Earth’s crust”, or “the noise made by the symbiotic real as such” (ibid.). Without that basic and ubiquitous, let’s say “deep ontological” level of solidarity, Morton wonders, “how can humans achieve solidarity even among themselves if massive parts of their social, psychic and philosophical space have been cordoned off? (…) Difficulties of solidarity between humans are therefore also artifacts of repressing and suppressing possibilities of solidarity with nonhumans”. As a result, to commit to solidarity today is “to feel haunted” by the suppression of our primordial solidarity with nonhumans. Letting go of human anthropocentrism leads one to recognize that human life is much “less spectacular, less grandiose, less vital … more ambiguous, more disturbing and more encompassing”. Human life, life in general, cannot, in fact, be contained within species boundaries, but rather is porous and always manifests itself as an assemblage of symbionts. What the discussion around the “Anthropocene” shows, in Morton’s view, is that “the imperial anthropocentric project – a project with human as well as nonhuman victims – is over, because we can’t think it anymore with a straight face”. Hence Morton’s appeal to kindness, since “being kind means being-in-solidarity with nonhumans: with kind-red”; it means including nonhumans as our “neighbours”. In this way, it is not merely possible to achieve solidarity with nonhumans, it rather means that “solidarity implies… and requires nonhumans … [in fact] solidarity just is solidarity with nonhumans”, or, to use Jacques Derrida’s phrase, a “solidarity of the living”.
To return to the pragmatic value of Morton’s extension and radicalisation of the concept of solidarity: it becomes clear that if one were to reread Rorty through a critical posthumanist or postanthropocentric lens à la Morton the opposition between “the desire for solidarity” and the “desire for objectivity” Rorty sets up shapes up somewhat differently. The liberal pragmatic desire for a truth that is good for “us”, given “our posthuman condition” between the fourth industrial revolution and the sixth mass extinction, is no longer separable from a desire for a “realist objectivity” in the form of what Morton calls the more-than-human “real” of deep ontological solidarity. The search for truth in the Anthropocene cannot be confined to human (and even less, humanist) communities but has to include from the start the nonhuman, the environment and the planet. What is “good for us to believe” is the object of a transformative posthumanist, postanthropocentric ecopolitics that takes Rorty at his word when he says: “For pragmatists, the desire for objectivity is not the desire to escape the limitations of one’s community, but simply the desire for as much intersubjective agreement as possible, the desire to extend the reference of ‘us’ as far as we can”. This also means overcoming some differences, namely the ones humanist anthropocentrism relies on and on which human exceptionalism is based, while embracing others, for example the fact that not all humans live (or even want to) in liberal pluralist societies. This includes the question of what “we” (i.e. the Rortyan “we” of white, Western, cosmopolitan… liberals) should do with that realisation, and what it means for the defence and future of the “Western” model of liberal democracy, which, it seems, is under threat both from “within” and from “without” and thus needs to be defended from both sides, at the same time. However, minimising anthropogenic climate change and avoiding extinction should be a good enough ecopolitical goal to construct new forms of solidarity around to begin with – without, hopefully, having to go through a new round of global wars over dwindling “resources”, now that “we” know that what used to be called by this name (i.e. resource) increasingly has to become part of the “us” of solidarity and will have to be attributed a subjectivity and an agency of its own.
 Richard Rorty, Contingency, Irony, and Solidarity, Cambridge: CUP, 1989, p. 198.
 Rorty, Contingency, Irony, and Solidarity, p. 189.
 Rorty, Contingency, Irony, and Solidarity, p. 189.
 Rorty, Contingency, Irony, and Solidarity, p. 191.
 Rorty, Contingency, Irony, and Solidarity, p. 192.
 Rorty, Contingency, Irony, and Solidarity, p. 195.
 Rorty, Contingency, Irony, and Solidarity, p. 198.
 Rorty, Contingency, Irony, and Solidarity, p. 192.
 Donna Haraway, Simians, Cyborgs, and Women: the Reinvention of Nature, New York: Routledge, 1991, pp. 149-182.
 Cf. Donna Haraway, The Companion Species Manifesto: Dogs, People, and Significant Others, Chicago: Prickly Paradigm Press, 2003. It is worth stressing that Haraway has always dissociated herself from the label “posthumanism”, stressing instead her preference for the solidarity of a “becoming with” (cf. e.g. When Species Meet, Minneapolis: University of Minnesota Press, 2008, p. 17) and “multispecies justice” (Staying with the Trouble: Making Kin in the Chthulucene, Durham: Duke University Press, 2016, p. 3).
 Timothy Morton, Humankind: Solidarity with Nonhuman People, 2017, p. 1.
 Morton, Humankind, p. 2.
 Morton, Humankind, p. 1.
 Morton, Humankind, p. 14.
 Morton, Humankind, p. 15.
 Morton, Humankind, p. 84.
 Morton, Humankind, p. 44.
 Morton, Humankind, p. 122.
 Morton, Humankind, p. 138.
 Morton, Humankind, p. 189.
 Jacques Derrida, La Solidarité des vivants et le pardon – Conférence et entretiens, ed. Evando Nascimanto, Paris: Hermann, 2016, pp. 125-126.
 Richard Rorty, Richard, “Solidarity or Objectivity?”, in Michael Krausz, ed., Relativism: Interpretation and Confrontation, Notre Dame: University of Notre Dame Press, 1989, pp. 167-183.
 Rosi Braidotti, Posthuman Knowledge, Cambridge: Polity, 2019, p. 2.
 Rorty, “Solidarity or Objectivity”, p. 169.