There's definitely something to the author's conception of modernity, but the story told in the quotes is only the half of it, as I understand it. Progress for the sake of heightened mastery over the world is definitely one of the hallmarks of modernity, but that in turn cannot be understood without the motivation that drove it, which was a profound anxiety and distress over where humans ultimately stood in the order of things, and especially the temporal order of things.

If, in pre-modernity, time was governed by stable cycles and repetition (of monarchic succession, of seasonal change, of flooding rivers), modernity changed the shape of time from a circle to an arrow - a past back there, a present now, a future, way out that way (the eschatological religions helped alot to bring this change about). The future no longer guaranteed by the cycles to which it had always been tethered, it is humans who become responsible for time: it is only what they do that determines the success of failure of what happens next. And this is as liberatory and it is terrifying. So to your author's focus on progress, I would add and supplement Stanley Cavell's focus on existence itself becoming problematic:

"The modern [is] ... a moment in which history and its conventions can no longer be taken for granted; the time in which music and painting and poetry (like nations) have to define themselves against their pasts; the beginning of the moment in which each of the arts becomes its own subject, as if its immediate artistic task is to establish its own existence. The new difficulty which comes to light in the modernist situation is that of maintaining one’s belief in one’s own enterprise, for the past and the present become problematic together. The modernist difficulty... is the difficulty of making one’s present effort become a part of the present history of the enterprise to which one has committed one’s mind, such as it is". (Cavell, Must We Mean What We Say)

All this is to say that the flip-side of mastery is a deep worry about non-mastery, of being swallowed up by an inexorable march of forward-facing time that threatens at every point to render any achievement meaningless (lost to time). Consider some famous modernist figures: Kafka, Beckett, Joyce, Mondrian, Dickinson, Rimbaud - these are authors and artists whose works are filled with a kind of frazzled disorientation, and rather than reflect any triumphalism over the world, express a deep unease with it. So progress and mastery, yes. But also (and underlying the need for progress) - deep and yawning anxiety. Or to quote Shoshana Felman: "Modernity inheres in its own problematic status. The energy
that destabilizes it is the energy of a relentless, never-ending question" ("You Were Right To Leave, Arthur Rimbaud: Poetry and Modernity" - my favourite essay on this subject).

Thanks for your comment. Very interesting !

Both quotes raise the point of modernity's relation to its past, its history. It was a deliberate break with the past, which creates problems and issues that did not arise when the present was contiguous with the past. A key feature was the attempt to establish knowledge, political life, and ethics on universal, independent reason. Since man is endowed with reason he is regarded as autonomous, his own authority.

"When the human subject masters reality by means of reason and/or science, the self comes to understand itself as existing in a fundamentally nominative mode. That is to say, the self becomes the subject that applies the disciplines of reason and science to the world, which is thereby conceived to be the object of that activity. This was in marked contrast to the epistemological model that prevailed in medieval theology. There, human beings understood themselves as existing in an accusative mode. They, and the wider reality of which they were a part, were created by God and were therefore, in a sense, objects of God’s creative activity. The only true ‘subject’, therefore, was God, the creator and ‘author’ of all known reality." — Matias

I see this conception of modernity as being very much a product of the European Enlightenment, elements of which, in turn, originated in the tradition which it inherited.

"the contemporary is intrinsically superior to the past because we have progressed from there to here. The modern way of thinking and acting is not simply an alternative way to that of antiquity; it marks a movement of improvement". — Matias

It's worth considering that 'idea of progress' was originally founded in the Christian idea of history as being a linear narrative, starting with Creation, and culminating the second coming and/or the Eschaton. This created a forward-looking culture which was fundamentally different from (say) Indian, Chinese and Persian cultures, which were founded on a cyclical notion of time (e.g. the 'yugas' or ages of Hinduism); and also the idea that the ancestral beings were the archetypes from which the present can only be a degeneration. I think this is one of the reasons that the scientific revolution and modernism originated in Europe (although that is of course contestable, and also probably not Politically Correct.)

However as Western culture developed, its religious origins were gradually modified or perhaps superseded by an altogether secular conception of progress ('secular' originally meaning 'the secular calendar' used to denote civil and public works, as distinct from 'the liturgical calendar') . I think one of the original articulations of the idea of 'culture progressing towards science' was Auguste Comte, founder of the social sciences, and also the originator of the term 'positivism', which is not coincidental. Comte articulated a theory of cultural progress through the 'religious stage', 'the metaphysical stage' and culminating in 'the positive stage'.The notion of progress from religious to scientific culture as underlying the notion of cultural development remains a very profound influence on modernity, even if Comte's particular ideas were subsequently criticized, abandoned or modified by later thinkers.

More could be said, but I want to make a point from the perspective of those critical of, or reacting against, modernism. A general observation I would make is that this phrase:

the self becomes the subject that applies the disciplines of reason and science to the world, which is thereby conceived to be the object of that activity.

denotes, as the author says, a kind of cognitive shift or change in world-view, which I think this is associated with the kind of anxiety that StreetlightX refers to above, and which I would describe in terms of 'the shadow cast by the Enlightenment'. A particularly incisive insight into this existential predicament was articulated by a philosopher who coined the phrase 'Cartesian anxiety':

Cartesian anxiety refers to the notion that, since René Descartes posited his influential form of body-mind dualism, Western civilization has suffered from a longing for ontological certainty, or feeling that scientific methods, and especially the study of the world as a thing separate from ourselves, should be able to lead us to a firm and unchanging knowledge of ourselves and the world around us. The term is named after Descartes because of his well-known emphasis on "mind" as different from "body", "self" as different from "other".

Richard J. Bernstein coined the term in his 1983 book Beyond Objectivism and Relativism: Science, Hermeneutics, and Praxis.

Many of the debates animating the 'culture wars' actually revolve around one or another form of this anxiety.

One resolution is fundamentalism: simply to cling to the traditional articles of faith, as if the Enlightenment never happened. Nihilism, relativism, scientism, and so on, are all possible, and indeed common, responses; (nihilism, by the way, might not be anything particularly dramatic or intense, just a shrug, a 'whatever'. It is simply the idea that nothing ultimately matters, or is ultimately real, which is more or less the same.)

The approach I try to take, however, is to try and understand the causes and consequences of this historical shift in thinking, from a viewpoint of neither fundamentalism, relativism or nihilism - as per this extended commentary on 'the Cartesian Anxiety' in The Embodied Mind, Varela, Rosch, and Thompson. In other words, to try and step out of, or resolve, the tension between tradition and modernity by adopting a philosophy than accommodate both; not an easy thing to do, but possible.

A particularly incisive insight into this existential predicament was articulated by a philosopher who coined the phrase 'Cartesian anxiety':

Cartesian anxiety refers to the notion that, since René Descartes posited his influential form of body-mind dualism, Western civilization has suffered from a longing for ontological certainty, or feeling that scientific methods, and especially the study of the world as a thing separate from ourselves, should be able to lead us to a firm and unchanging knowledge of ourselves and the world around us. The term is named after Descartes because of his well-known emphasis on "mind" as different from "body", "self" as different from "other". — Wayfarer

Yes, Descartes is a pivotal figure in the development of the idea of ontological dualism, the radical separation that begins with Plato. That dualism, coupled with the linear, eschatological model of time that is primarily associated with the Judaeo-Christian tradition, is the source of the existential anxiety of separation and the consequent apprehension of the need to control what has ever-increasingly come to be seen as a hostile nature.

The rationalism that grows out of the vision of humans as being most fundamentally disembodied souls and then later disembodied intellects neurotically demands an impossibly static, perfect and incorruptible understanding and control of a dynamic world, including the human world. This quest, along with the "fortuitous" discovery of cheap energy sources in the form of fossil fuels has enabled a spectacular and, until the present, rapidly accelerating development of technology and science which has arguably served to distance humanity further from the natural world, and brought it to come to see the world more and more in terms of scarcity instead of providence.

Accompanying this increasing tendency to view the world as hostile, (viz e.g. Hobbes) and its abundance of resources through an increasingly anxious lens, which comes to see instead threatening scarcity and comes to feel growing insecurity, has been the inevitable rise of capitalism with its carving up of the world in terms of private ownership, and the ongoing monetization of all available human activities and services.

So existential anxiety is no surprise in view of the ever-increasing fracturing of perspectives which has culminated in the contemporary world. What I have written here is a very simplistic account of what has been an almost unthinkably complex story. Today human life has become so complex that it surpasses our capacity to comprehensively understand it and the chimera of control is becoming ever more obvious as such to those who do not remain in ignorance or denial (which unfortunately is most of the populace including its political and intellectual leaders).

Now no one really knows what to do, and so everyone clutches at their own preferred straws in order to distract themselves from the real situation of, among many other other dangerous factors; dwindling resources, the imminent end of cheap energy, the exponential increase of debt and the accelerating devastation of the natural world and the extinction of flora and fauna, and the inevitable erosion of prosperity that goes along with those.

There you have it in a nutshell: modernity.

When the human subject masters reality by means of reason and/or science, the self comes to understand itself as existing in a fundamentally nominative mode. That is to say, the self becomes the subject that applies the disciplines of reason and science to the world, which is thereby conceived to be the object of that activity. — Matias

It was probably quite predictable that a bout of scientific and technological progress would make some people, and even cultures, much more arrogant than they used to be.

Just like Moore's law on exponential growth in computer CPU speed was inevitably going to come to an end some day -- it already did at least a decade ago -- economic growth and growth of per capita income will also soon disappear. The flurry of impressive new discoveries in nuclear physics, for example, also came to an end at least fifty years ago, and nobody is sending people to the moon any longer.

We could easily be entering an era of mere stagnation. Still, the future could even be worse than that.

Quire a few short-term decisions in the style "after me the deluge" are increasingly getting burdened by their long-term consequences.

For example, most of the existing nuclear plants around the globe are about to reach the end of their useful lives. At that point, they will no longer make money, but they will still need to be decommissioned at enormous expense. I can guarantee that it is not the people who have made lots of money from these nuclear plants when they were still operating, who will pick up any of the decommissioning cost. That problem will have been trivially predictable. You could see it coming from the get-go, but that will not make any difference as to what is inevitably going to happen, and who exactly will be on the hook for the gigantic decommissioning bills.

The worst arrogance can undoubtedly be found in the social sphere. People no longer need children, because the government will take care of them in their old age. And where is the government going to find the resources to do that? Well, obviously, from other people's children!

So, there is a hell of a lot of fundamentally arrogant stuff that is simply not going to keep flying. We can probably not afford positivism.

The main thing I'd emphasise throughout all the things mentioned is a changed relationship with time, in which the human relationship with time gets put into question in a way which it never was before. Or, as one of my favourite ways of characterising modernity has it: to be modern is to be able to speak about the modern.

Also, while it's a common story that it was the eschatological religions that helped linearize time, there's some interesting historical work showing that religious time arose as a reaction to the already linearized time of the Selecuids, for whom time was a line without any redemption at the end of it: that eschatological time was meant to humanize time again in the face of it's inhuman march, make it manageable and comprehendible:

"The theological and political roots of ‘apocalyptic eschatology’, as this end-times literature is known, are complex and multiple. An entire subfield of Second Temple and early Christian scholarship is devoted to this problem of emergence. But the Seleucid Era has played no role in existing research within either classical ancient history or biblical studies. I suggest that the ubiquitous visibility and bureaucratic institutionalisation of an irreversible, interminable and transcendent time system provoked, as a kind of reaction-formation, fantasies of finitude among those who wished to resist the Seleucid empire. The only way to arrest the open-futurity and endlessness of Seleucid imperial time was to bring time itself to a close." (source)

Religions unsurprisingly here playing the role of reacting against modernity, or of turning it against itself for its own ends.

Religions unsurprisingly here playing the role of reacting against modernity, — StreetlightX

According to Gavin Hyman (the quote in the OP is from his book) this is a misconception, because the linear time was already dominant during the Middle Ages, but what changed was the way people conceived of God. Modernity as we know it is therefore a child of (Christian) religion, even if centuries later Christian authorities have done all they can to 'catch' this child and neutralize it.

What changed (according to Hyman) was:
"The advent of modernity brought with it a transformed conception of God, a distinctively ‘modern’ theism. When God is understood to be an object of thought, then God is created in the image of humanity. God comes to be conceived in human terms, his transcendence is domesticated and, in some instances at least, God increasingly takes on the characteristics of a ‘big person’. In effect, God becomes a projection of the human subject."

"The advent of modernity brought with it a transformed conception of God, a distinctively ‘modern’ theism. When God is understood to be an object of thought, then God is created in the image of humanity. God comes to be conceived in human terms, his transcendence is domesticated and, in some instances at least, God increasingly takes on the characteristics of a ‘big person’. In effect, God becomes a projection of the human subject. — Matias

Hmm, this genealogy seems off to me. Gods were always conceived of as human-like (see the Greek and Roman Gods), only with powers and long lives and whathave you (the occasional extra arms or animal visage too). I always understood the 'inhumanization' of God to take place precisely with the advent of the religions of the Book, which made God either so inhuman as to be accessed only in mystical ecstasy (negative theology), or else by way of analogy (Aquinas) where God (singular) was at best analogous to man (always man), without being univocal with him.

Gods were always conceived of as human-like (see the Greek and Roman Gods), only with powers and long lives and whathave you — StreetlightX

True, but could it be the combination of linear time plus the conception of God as object (no longer subject of the world and all its events) that initiated the first and decisive steps towards what became the early modern period?
The two sides changed roles: During the Middle Ages Man was the object of God the Almighty, then Man discovered his power and became the subject whereas God was more and more the object of human conception and action ?

The two sides changed roles: During the Middle Ages Man was the object of God the Almighty, then Man discovered his power and became the subject whereas God was more and more the object of human conception and action ? — Matias

This is a bit obscure to me. It's not clear that the subject-object distinction fits here (more appropriate seems to me to be something like principal-agent), nor its role in characterising modernity.

I’ve just started reading a book by Charles Baudelaire, ‘The Painter of Modern Life’ which has the line “modernity is the transient, the fleeting, the contingent”

It’s on the Penguin’s Great Ideas list if you want to take a run at it. Easy reading :)

"The advent of modernity brought with it a transformed conception of God, a distinctively ‘modern’ theism. When God is understood to be an object of thought, then God is created in the image of humanity. God comes to be conceived in human terms, his transcendence is domesticated and, in some instances at least, God increasingly takes on the characteristics of a ‘big person’. In effect, God becomes a projection of the human subject." — Matias

A review notes:

Hyman distinguishes early modern and medieval theologies. In Thomas Aquinas’s prototypically medieval conception of God, terms do not apply the same to creatures as they do to God (univocal predication). Speaking univocally about God and creatures would involve applying created categories to a God that transcends all created categories. Yet the terms that apply to God cannot be divorced from creaturely languages (equivocal predication). If they were, creatures would be incapable of ever speaking about or believing in God. Aquinas’s solution was that predication is neither univocal nor equivocal of God and creatures, but analogical.

According to Hyman, Thomistic analogical predication was neglected in early modernity so that God was either spoken of univocally or equivocally. Speaking of God in these two ways renders theism vulnerable to atheistic arguments. For example, univocal predication opens theism to the Problem of Evil: if the term ‘good’ is applied univocally of God and creatures, and if humans are obligated to prevent suffering to the degree that they are able, then, a fortiori , so too would a benevolent and omnipotent deity. Yet vast suffering exists in our world, so God, the argument goes, does not. The Problem of Evil dissolves if the term ‘good’ (and all other terms) mean something different when applied to God than when applied to creatures