Reference: (Not that I agree with it) Wikipedia: Criticism of Humanism:
Polemics about humanism have sometimes assumed paradoxical twists and turns. Early-20th-century critics such as Ezra Pound, T. E. Hulme, and T. S. Eliot considered humanism to be sentimental "slop" (Hulme)[citation needed] or "an old bitch gone in the teeth" (Pound).Postmodern critics who are self-described anti-humanists, such as Jean-François Lyotard and Michel Foucault, have asserted that humanism posits an overarching and excessively abstract notion of humanity or universal human nature, which can then be used as a pretext for imperialism and domination of those deemed somehow less than human. "Humanism fabricates the human as much as it fabricates the nonhuman animal", suggests Timothy Laurie, turning the human into what he calls "a placeholder for a range of attributes that have been considered most virtuous among humans (e.g. rationality, altruism), rather than most commonplace (e.g. hunger, anger)". Nevertheless, philosopher Kate Soper notes that by faulting humanism for falling short of its own benevolent ideals, anti-humanism thus frequently "secretes a humanist rhetoric".
In his book, Humanism (1997), Tony Davies calls these critics "humanist anti-humanists". Critics of antihumanism, most notably Jürgen Habermas, counter that while antihumanists may highlight humanism's failure to fulfil its emancipatory ideal, they do not offer an alternative emancipatory project of their own. Others, like the German philosopher Heidegger. considered themselves humanists on the model of the ancient Greeks but thought humanism applied only to the German "race" and specifically to the Nazis and thus, in Davies' words, were anti-humanist humanists. Such a reading of Heidegger's thought is itself deeply controversial; Heidegger includes his own views and critique of Humanism in Letter On Humanism. Davies acknowledges that, after the horrific experiences of the wars of the 20th century, "it should no longer be possible to formulate phrases like 'the destiny of man' or the 'triumph of human reason' without an instant consciousness of the folly and brutality they drag behind them". For "it is almost impossible to think of a crime that has not been committed in the name of human reason". Yet, he continues, "it would be unwise to simply abandon the ground occupied by the historical humanisms. For one thing humanism remains on many occasions the only available alternative to bigotry and persecution. The freedom to speak and write, to organise and campaign in defence of individual or collective interests, to protest and disobey: all these can only be articulated in humanist terms."
Modern humanists, such as Corliss Lamont or Carl Sagan, hold that humanity must seek for truth through reason and the best observable evidence and endorse scientific skepticism and the scientific method. However, they stipulate that decisions about right and wrong must be based on the individual and common good, with no consideration given to metaphysical or supernatural beings. The idea is to engage with what is human. The ultimate goal is human flourishing; making life better for all humans, and as the most conscious species, also promoting concern for the welfare of other sentient beings and the planet as a whole. The focus is on doing good and living well in the here and now, and leaving the world a better place for those who come after. In 1925, the English mathematician and philosopher Alfred North Whitehead cautioned: "The prophecy of Francis Bacon has now been fulfilled; and man, who at times dreamt of himself as a little lower than the angels, has submitted to become the servant and the minister of nature. It still remains to be seen whether the same actor can play both parts".
Sentientist philosophers criticise humanism for focusing too strongly, sometimes even exclusively, on the human species. They propose sentientism as an extension of humanism that grants degrees of moral consideration to all sentient beings—those capable of experiencing. Sentient beings include humans and most non-human animals and could potentially include artificial or alien intelligences."