Replying to myself to address several different replies.

I see history as a "hard-enough" science. You can gather a lot of various evidence, use a lot of tools based on science (carbon-14 dating) and evidence published by others to understand a plausible scenario and extend it through new theories. I suppose this is what was also meant by "empirical." Unlike some science goal such as describing the orbit of the planets or the nature of our galactic center, history tries to find true statements about the past.

Even more realistic than the Lincoln example is the historicity of Jesus [1]. Billions of people talk about a person who lived 2000 years ago and we don't know whether he was a real person or not. Either he existed or he didn't, and we can apply many tools of historical study to try to find an answer. And the best we have is that theories for it that seem stronger than those against it.

When I wrote that the comment [2] was "practically anti-science", I was referring to the pop-science aspect of it, where you just have to present some new and flashy idea to get attention. I'm also a proponent of viewing pre-historic humans to be just as intelligent, complex, and capable as modern humans, so I mostly agree with the ideas of the comment. For example, the colonization of Pacific islands by Polynesian navigators over vast expanses of open water is well attested. But just pointing this out is not sufficient. You need an entire scenario (theory) of what plausibly happened: the climate was thus, and the terrain was thus, and this supported X humans who moved thus, and that explains the population numbers we see later, and all this has to be based on archaeological and geological evidence.

I think I was reacting to the tone of the comment, mostly. It struct me as the slightly informed personality who jumps into a scientific debate with his own pet theories and criticizes the others for not considering them. I think it's safe to say that the researchers who work in these fields have probably considered these pet theories, and are working on their own theories for a variety of reasons (no evidence, not realistic, or simply too busy with lots of work to investigate that line of thought at this time). The comment seems to believe the researchers did not consider these theories, when in fact we don't know whether they considered them or not.

I'm all for popular input into science, and I actually identify as a person who spends 10 minutes on Google/Wikipedia (and HN articles) to understand something. Often these people have a broad range of interests and can bring in ideas and details that may be overlooked. And I even celebrate people like Thor Heyerdahl who float new theories and go the extra mile to experiment and provide new evidence. But they can't jump in the middle of a scientific debate and claim to have it all figured out and have people take them seriously.

So whether it's a comment on HN or somebody's pet theory in a book, I feel it has to respect and acknowledge the existing science and provide evidence for itself, and avoid the sensationalized or know-it-all tone of pop-science.

[1] https://en.wikipedia.org/wiki/Historicity_of_Jesus
[2] https://news.ycombinator.com/item?id=12562466