I find the following passage to be very expressive.
The grounds of philosophical idealism, the control of nature itself, has lost the certainty of its omnipotence precisely because of its unstoppable expansion during the first half of the twentieth century; as much because the consciousness of human beings lagged behind and the social order of their relationships remained irrational, as because it took the measurement of what was achieved, whose minuteness was measurable only by comparison to what was not achievable. The suspicion and presentiment are universal, that the control of nature weaves ever more tightly through its advance the catastrophe which it also intended to ward off; the second nature, into which society has overgrown.
In relation to the idealist goal, which is “the control of nature”, notice he proposes two reasons for the loss of “the certainty of its omnipotence”. The first mentioned, the consciousness lagged behind in its understanding of social order and its relationships because they remained irrational. The second, achievements could only be measured in comparison with what was not achievable. The activity derived from the ideal goal of controlling nature then weaves within itself, the catastrophe which it intended to avoid, “the second nature”.
The second nature is not at all explained, and this is my first acquaintance with it.
So “the second nature” appears to me to refer directly to the artificial. There is a traditional distinction between the natural, and the artificial. Demarcation was never well defined, because the products of living things other than human beings were consider to be natural, while the products of human beings were artificial. And Aristotle had intentionally blurred the boundary by comparing how natural things come into existence through potential (oak tree from an acorn) in a way similar to how artificial things come into existence through the artist’s intention (teleology).
With the advent of evolutionary theory, the boundary between natural and artificial has been functionally dissolved, as human beings are now natural, therefore their products are considered to be natural. But they take the character of “second nature”. Now this sort of leaves intention, final cause, and teleology as ungrounded, floating freely, with nothing to be attributed to. So the ancient grounding of intention, as the property of an individual human being producing artifacts, is replaced by a grounding in society as a whole, where intention and final cause originate in society, act through ideology as downward causation, as “the ‘heteronomous’ social totality that brutally or insidiously imposes itself on individuals from above or from without”.
Of course this is just a continuation of the social structure produced by theology, within which the Will of God acts through the clergy, through the rulers, subordinating the individual subjects. Without “God” though, the source of intention is undefined and the structure is unintelligible.
After introducing that concept, “second nature”, he goes on to explain the subjective feeling of powerlessness which reinforces the bane of second nature. This produces a naive belief in being, “membership-in-being”, which I assume is a substitute for a true understanding of relationships of social order which remain irrational to the subjects. They feel like they’re facing “the all”, but they actually cling to the particular, and this reinforces their weakness which makes them feel like they’re facing the All. This is a sort of trap, a cage or prison, which he calls “the subjugation of the subject under being”.
So he ends with a paragraph about how the bane can be lessened, if, in Hegel’s words, the subject is “somehow there”. What strikes me is that he now turns to what is “achievable”, in contrast to the beginning of the chapter where he says certainty is lost due to achievements being measured in relation to what “is not achievable”.
The delimitation of the Spirit to what is open and achievable in its historical level of experience is an element of freedom; non-conceptual meandering embodies the opposite.
And that is followed up with:
Doctrines which unhesitatingly run away from the subject into the cosmos are along with the philosophies of being far more compatible with the hardened constitution of the world, and the chances of success in it, than the slightest bit of self-reflection of the subject on itself and its real imprisonment.
Notice, “far more compatible with the hardened constitution of the world”. Those are the determinist doctrines, determinism forcing what is not achievable. The “self-reflection of the subject on itself and its real imprisonment” are the philosophies of free will.