I think in this book Sam overlooks the evidence showing that the scientific, secular industrial age may be objectively more irrational and immoral than even the most backward and brutal of medieval religious societies.
Its greater degree of immorality can be expressed with a single word: ecocide - here argued as an intrinsic feature of even the most rational of industrial mass societies.
Its greater degree of irrationality can be expressed with the word “unsustainability”.
In other words, a type of society that is unsustainable functions in a fundamentally irrational framework, even if some aspects of the society like science can solve other (or even all) less fundamental problems rationally.
In contrast, a type of society that is sustainable works in a fundamentally rational framework, even if most other less fundamental aspects of life are irrational.
Similarly, a type of society that is ecocidal functions in a fundamentally immoral framework, even if many other aspects of society are morally admirable.
And conversely, a type of society that is not ecocidal functions in a fundamentally moral framework, even if many other aspects are morally reprehensible.
Yes, a brutal medieval society was more immoral in its behavior to humans, and probably more immoral toward a (comparatively small) number of animals. But since humans are only 1 species and ecocide entails the destruction of countless species whose total collective value can reasonably said to be greater than humanity’s, the total amount of immorality is actually greater.
Here 3 questions arise:
1) How do modern humans influence the joy-to-suffering (or pain-to-pleasure) ratio of other species as compared to a) other predators in nature, and b) the medieval society.
2) How much greater is the number of extinctions that modern human existence entails as compared to that of a) other predators and b) the medieval society
3) How much does the extra population that arises out of industrial society (due to medical advances, increasing food production etc) increase the amount of farm animal suffering.
As for the greater degree of irrationality, we can start with 1 question:
Is life worth living for an average member of a brutal medieval society?
If the answer is even a reluctant yes, then the society may be said to be more rational than ours for the simple fact that it is actually ecologically sustainable and so it can, in theory, keep going for a very long time.
In other words, let’s say that from a spectrum of 1 to 10, with 1 being “barely worth living” and 10 being “amazing life”, the average medieval era individual scores a 2 and an average modern individual scores a 7.
But let’s say that modern society goes extinct (due to unsustainability) in 200 years, but the sustainable medieval society keeps going for 200,000 years.
We have to multiply 7 by the number of modern people by the number of years they’d live those 200 years, and compare the resulting number to 2 multiplied by the number of medieval people, by the number of years they’d live those 200,000 years.
The medieval era number is much greater.
And even more so if we compare modern society with other societies (e.g. prehistoric hunter gatherer society) that are in many ways less objectionable than medieval society, and, as we know from various calculations, produced most of the people who have ever walked the earth.
All this analysis can be placed within a theory that Harris also seems to overlook or underestimate: Terror Management Theory. This theory has gathered a substantial amount of evidence (see vid & paper at the end) and defines human culture (whether religious or secular) as a series of quasi-arbitrary activities and beliefs that sustain a fundamental death-denying illusion: That we are persons of value in an enduring world of meaning.
And while religious culture attempts to acquire this illusion through notions of literal immortality and cosmic personal significance, secular culture does so through notions of symbolic immortality (legacy) and earthly personal significance.
Our faith in progress seems to be one of these illusions. With the idea of progress we sought what theists found in the idea of providence: An assurance that history would not be meaningless.
The idea that history is cyclic can render any progress obtained meaningless because then ultimately there is only moral gain and loss.
We did not want to be confronted with regression and wanted to believe that history is not cyclic, but progressive.
The idea that “we’ve come a long way” despite increased unsustainability and ecocide imbued the course of history with meaning, purpose and continuity.
p.s. With my previous post correcting Harris’ “perfect weapons” argument (with “perfectly equal weapons” & “super imperfect weapons” additional arguments), I think I added to Chomsky’s contribution in showing that Harris also does place faith (i.e. belief not backed by evidence) in the goodness of his own nation. This nationalism, like progress, is also a form of secular faith.
p.s. 2 Another thing that can be said in favor of religious society, especially primitive hunter-gatherer society, is that it does offer a greater relief from existential death anxiety than secular society.