One interesting essay on the history of some philosophies and worldviews you might like is Eric Vogelin's Science, Politics and Gnosticism (1968). Here he traces a lot of modern thought back to the early Gnostic religion. The lack of self-reflection and particularly the righteousness I see today makes me think his point is very accurate.

For further reference: http://www.shadowstats.com/alternate_data/inflation-charts

I get why your assumption they disregarded sentiments exists; we are living in very similar times where undue public importance is given to sentiments. And we would like to think they were completely different to us, but the reality is we live in similarly sentimental times.

Edit: looked up on the author of that review, https://en.wikipedia.org/wiki/Herbert_Ihering, apparently liberal-left leaning and not a darling of the Nazis.

PS. if you want a trip into weirdness, watch the uncut version of Metropolis. Weird mystic religion they got over there.

Cause I hope they do have a theory that connects to their personal values, otherwise they are just following blindly.

PS. did you just make up "factual belief"? I mean it is a tautology on many levels. But let's take it as qualified belief. Isn't that the root of religion? It's okay, we humans need to believe in something

Btw, even taking a very atheistic perspective, only focused on how humanity evolved (which is a selfish process in spite of your future protestations of how you have trascended it) we can see we evolved to be nice only out of self-preservation.

One would think that is the ultimate personal gain but I'll grant you that reminding yourself you are a good person must be a psychological gain of its own.

And they do proselytize quite a bit. The average atheist is as separate from the process of science as the average NFL fan is from actually scoring a touchdown. They're both spectators under a similar set of illusions regarding their claims as to their relevance in each ones game. Go TEAM SCIENCE!!!