John Derbyshire gives the following as examples of reality denial:
All but a very tiny proportion of human beings are biologically male (an X and a Y chromosome in the genome) or female (two X chromosomes). A person who is biologically of one sex but believes himself to be of the other is in the grip of a delusion. That is what everybody would have said 50 years ago.
Some of those who said it would have followed up with an expression of disgust; some with unkind mockery; some with sympathy and suggestions for psychiatric counseling. Well-nigh nobody would have said: “Well, if he thinks he’s a gal, then he is a gal.” Yet that is the majority view nowadays. It is a flagrant denial of reality; but if you scoff at it, you place yourself out beyond the borders of acceptable opinion.
It is, of course, the same with race. I still blink in disbelief when I hear or read someone saying, “There is no such thing as race.” It falls on my ears much like “There are no such things as mountains,” or “There is no such thing as water.” Of course there is such a thing as race. Until recently, everyone knew this. As I like to remind people, the founder of the modern biological sciences surely knew it.
[. . .]
Reality denial is rampant on the Left. Part of the explanation, according to Derbyshire, is the decline of religion. The rise in reality denial is due to the decline in religion!
Derb's idea is that in the past religion functioned like a lens to focus our wishful thinking on one nonexistent object, God, or rather on one set of nonexistent objects (God, angels, devils, incarnate, pre-incarnate, and dis-incarnate spirits) to the exclusion of all other nonexistent objects. But with the decline of religion, the urge to deny reality becomes unfocused and can take almost any object, including denizens of the sublunary:
Religion as a lens: When people stop believing in God, the old quip goes, they don’t believe in nothing; they believe in anything.
Very serious, practical people—statesmen, generals, industrialists, engineers—often used to be deeply religious, holding the unreal—the transcendent, if you want to be polite—corralled in one part of their mind while the rest grappled with reality. Religion focused wishful thinking—kindly Sky Fathers listening to our prayers, wisps of immortal spirit-stuff in our heads—into a coherent set of ideas and habits.
With that focusing lens gone, wishful thinking runs amok. “I feel female/black, so I am female/black!” “Race creates tensions we don’t know how to manage, so let’s pretend it doesn’t exist!”
Nothing is real
And nothing to get hung about.
Strawberry Fields Forever . . . .
An Alternative Theory
As a theist, I cannot of course accept Derbyshire's partial explanation of leftist reality denial. I of course agree that people engage in reality denial and wishful thinking, and I accept the examples given above as examples of reality denial.
So here is an alternative partial explanation.
Atheists presuppose truth. That is, they presuppose that there is a total way things are that does not depend on the vagaries of human belief and desire. (An atheist will be quick to point out that desiring that there be a Heavenly Father is a very bad reason for thinking there is one.) The characteristic atheist claim is that the nonexistence of God is a part of the way things are. Theists, most of them anyway, also presuppose that there is a way things are. Their characteristic claim is that the existence of God is a part of the way things are. The common presupposition, then, is that there is a total way things are. The question is not whether there is truth, but what the truth is. The question is not whether there is a total way things are; the question is which states of affairs are included in and which excluded from the total way things are.
The death of God, however, brings in its train the death of truth as Nietzsche himself fully understood. The loss of belief in the Christian God calls into question whether there is truth at all. For God is not just another being among beings, but the source of the Being of every being other than God, as well as the source of the intelligibility and value of every being other than God. But nothing is intelligible unless there is truth to be discovered. As Nietzsche saw, if there is no God, then there is no truth. And if no truth, then no intrinsic intelligibility. Next stop: perspectivism, Nietzsche's central epistemological doctrine. (The God-truth linkage can be rigorously argued in various ways; here is one.)
Once truth goes by the boards, then nothing counts as true or real except what we want, desire, interpret in line with our interests, socially construct, or what enhances the feeling of power in us, 'empowers us' to use a leftist-POMO turn of phrase with roots in Nietzsche's perspectivism. As Nietzsche writes in The Will to Power #534:
Das Kriterium der Wahrheit liegt in der Steigerung des Machtgefühls.
The criterion of truth resides in the heightening of the feeling of power.
Once we get to this point in the history of the death of God/truth, a boy can choose to become a girl, and a white a black. Hell, a white boy could choose to become a black girl! Why not? You just identify yourself that way, there being no fact of the matter to prevent you from choosing any self-identification you like. Hence the absurdities decried by Derbyshire and the rest of the coalition of the sane, the absurdities of transgenderism and transracialism.
God, I am urging, is the support of the way things are. Kick away that support and Being dissolves into a Heraclitean flux of opinions and perspectives.
Summary
The fact that wants explaining is the fact of leftist reality denial. Two different explanations:
Derbyshire: Time was when wishful thinking was focused on God and other nonexistent objects of religion. But God is now dead culturally speaking, among the elites of the West. (And this is good because, in fact, there is no God.) The need for wishful thinking, however, remains strong. It gets shunted onto sex and race and the results are the reality-denying absurdities of transgenderism ansd transracialism.
Vallicella: God is real, but no longer believed to be real by the elites in the West. Man, seduced by the life-extension consequent upon advances in medical technology, and mesmerized and held in thrall by his 24/7 all-invasive and -pervasive communications technology, can no longer bring himself to believe in anything beyond the human horizon. The human horizon seems to extend limitlessly. The death of God, however, brings with it the death of truth, and this opens the floodgate to any and all perspectives which are 'true' only in the sense that they reflect the identities and the power demands of those who are the subjects of the perspectives.
In short: God is not the focus of our wishful thinking in such a way as to keep the rest of out thinking focused on reality; God is the support of truth and reality and thus the presupposition of the distinction between wishful thinking and reality-oriented thinking.