https://en.wikipedia.org/wiki/Optical_telegraph preexisted the electric telegraph for speed of information over land. (Although it has some related systems, such as heliographs.)
I'd guess materials science as a field with several discontinuous leaps. Bessemer process, duraluminium, carbon fiber reinforced plastics: I think these are the most famous candidates. (It's hard to put it into metrics, but nearly all non-immobile things were structurally built out of wood until Bessemer/Martin steel came around.)
Rocketry is intimately related to nuclear bombs. The impetus to develop it came from the fact that now a small payload could destroy a city. (In WW2, a V2 occasionally leveled an apartment block or two. This is not a performance that justifies investing in an ICBM.) The early space race was largely a demonstration of this capability, as a rocket capable of accelerating a multiple-ton payload into near-circular orbit required to hit the other side of the earth is necessarily capable of accelerating a few-hundred-kg payload into low earth orbit, and vice versa.
https://en.wikipedia.org/wiki/Duga_radar for power used in an active sensor (mostly searchlights and radars)?
Regarding Africa, late 19th century technology solved at least *two* crucial problems that prevented European takeover before. One was that Europeans themselves would die to tropical diseases, solved by quinine. The other was that Europeans' *horses* died to nagana (known as sleeping sickness in humans), solved by steam riverine ships.
I think a part of the observations are better explained by Harry (any a few other characters) being at Kegan stage 5. Without going into the rest of the theory (which I think messed up stages "3" and "4"), consider three concepts of property:
Harry, Quirrell, Dumbledore, and some other characters are very clearly thinking in the last mode. This mostly explains points:
No experience, just an idea: create a line of retreat for a "smaller version" of the topic before confronting the whole, to make the concept more available. First, answer "what would you do if it turned out that you(r friends) were mistaken about some minor details of God", and only after that ask about nonexistence. (I'd guess that more iterations would be seen as condescending.)
There isn't, and the article is committing a type error. The terrain isn't a map, reality isn't a model/theory.
Unless you are using a model to approximate the behavior of a system that is of exactly the same kind, i.e. using a computational model to approximate another computational thingy, in which case you could indeed have the model that exactly coincides with what it is to describe. This may even be useful, e.g. in cryptography. But this is an edge case.
To be charitable to the postmodernists, they are overextending a perfectly legitimate defense against the Mind Projection Fallacy. If you take a joke, and tell it to two different audiences, in many cases one audience laughs at the joke and the other doesn't. Postmodernists correctly say that different audiences have different truths to "this joke is funny" and this state of affairs if perfectly normal. Unfortunately, they proceed to run away with this, and extend it to statements where the "audience" would be reality. Or very charitably, to cases of people comparing quoted statements, where it is again normal to remind the arguers that different people can have different maps. Of course, it would be far more helpful to tell them to compare the maps against reality, if indeed there is anything the maps claim to be maps of.
"Three of their days, all told, since they began speaking to us. Half a billion years, for us."
I think this severely breaks the aesop. In three frames, hum-AGI-ty learns the laws of the alien universe. But then the redundancy binds, and over the next hundred thousand frames ("It's not until a million years later, though, that they get around to telling us how to signal back.") humanity learns little more than how to say "rock". Then "it took us thirty of their minute-equivalents to [...] oh-so-carefully persuade them to give us Internet access", altogether 3*10^6 years up to that point.
I'm putting it here, because the insight clicked when reading this article: perhaps one of the most important of "our" characteristics is simply being bad at compartmentalization?
"The New Atheists contend that the beliefs we hold have consequences for our conduct." -- Let's assume this view is basically typical mind fallacious, and the majority mostly compartmentalize away their religious beliefs. (Beliefs-as-attire, to be worn in the appropriate context only.) What would happen to those people who don't natively do this?
Recognition that the so-called "repugnant conclusion" isn't repugnant at all. Total utility maximization involves an increase in the population---eventually, not necessarily right now---as most human lives have positive subjective utility most of the time (empirically: few people commit suicide).
Reductio ad absurdum: what would the universe be worth without humans in it to value it? Lesser reductio: what would a beautifully terraformed planet be worth, if humans were present in the universe, but none on that planet?
Additionally, beyond the "material" ("industrial"?) aspect, people derive much of their enjoyment of life from social interactions with other people; it would be remiss not to use this nigh-inexhaustible source of utility. This category just so happens to include, among other things, the joy of being with one's children.
"There's no third-party experiment you can perform to tell you the answer."
While it's irrelevant to the anthropics/quantum physics debate, I almost immediately thought: let's put an electrode onto one side of an Ebborian brain-paper, and give it a train of pulses while it splits. Ask the Ebborian that "inherits" the other side of the brain, how many pulses it experienced.