Science and technology
The Day of the Triffids touches on mankind's advances in science and technology as a possible contributor to the collapse of society that's depicted in the novel.
I saw them now with a disgust that they had never roused in me before. Horrible alien things which some of us had somehow created, and which the rest of us, in our careless greed, had cultured all over the world, One could not even blame nature for them.
— Bill Masen, in The Day of the Triffids
In a master's thesis entitled Social Critique in the Major Novels of John Wyndham: Civilization's Secrets and Nature's Truths,[21] Michael Douglas Green writes about other scientific contributions to the novel's apocalypse:
The apocalypse in The Day of the Triffids is not merely a result of the creation of the triffids, however. It is instead, a sort of compound disaster; the triffids only gain free rein after another man-made horror—a satellite—goes awry. The narrator describes the advent of a sort of orbital missile (not utterly unlike an ICBM) developed in both the East and West carrying not only atomic weapons but also "such things as crop diseases, cattle diseases, radioactive dusts, viruses, and infections not only of familiar kinds, but brand-new sorts recently thought up in laboratories, all floating around up there."
— Social Critique in the Major Novels of John Wyndham: Civilization's Secrets and Nature's Truths, pp. 28–29
Post-WWII British politics
Critics have highlighted the parallels between the triffids and the decolonization that took place in Europe after 1945. In an essay entitled "The Politics of Post-Apocalypse: Ideologies on Trial in John Wyndham's The Day of the Triffids",[8] literary critic Jerry Määttä writes:
It could be argued that one of the reasons why John Wyndham's The Day of the Triffids reached such a vast audience is that it can be read as a symbolic negotiation of the British situation in the first few years after the Second World War. Elsewhere, I have also suggested that the curiously under-analysed triffids could be read as distorted metaphors for the colonised peoples of the British Empire—then in the middle of the process of decolonisation—coming back to haunt mainland Britain, much as the Martians did in H. G. Wells' The War of the Worlds (1898), one of Wyndham's main influences.
— The Politics of Post-Apocalypse: Ideologies on Trial in John Wyndham's The Day of the Triffids 13.2, "The Politics of Post-Apocalypse: Ideologies on Trial in John Wyndham's The Day of the Triffids"
Robert Yeates, in his essay "Gender and Ethnicity in Post-Apocalyptic Suburbia",[22] proposes another connection to colonialism:
The title The Day of the Triffids shows a colonial role reversal of this kind in which humanity is no longer the most powerful species, and Masen remarks that it is "an unnatural thought that one type of creature should dominate perpetually."
— "Gender and Ethnicity in Post-Apocalyptic Suburbia", p. 112
At the time of the novel's writing there was an emerging welfare state in Great Britain after the formation of the Attlee ministry. Coker's forced shackling of sighted people to the blind echoes the sentiments that some middle-class British citizens felt in the wake of the changes introduced by the Labour party after their 1945 election victory.[8]
Loss of identity
The novel frequently brings into question the utility of individualism during the apocalypse. Colin Manlove highlights this phenomenon in his essay "Everything Slipping Away: John Wyndham's The Day of the Triffids":[23]
Simultaneous with this process, people lose their identities. Part of this comes from the fact that all now exist in a shared situation, the catastrophe: no longer can one be an agronomist, a doctor, a farmer, a novelist, but only one more individual up against the triffids, one only real distinction being if one is sighted.
