I suspect this Ayan Rand quote is a knee-jerk response to the idea that there is no "pure objectivity" in scientific and historical research.
What my OP is entirely consistent with -- and (I think) needs in order to be justified -- is:
- a belief that the fundamental principles of formal and informal logic are valid and necessary -- "true", if you like, and that they apply universally. Without these there can be no rational discourse or profitable exchange about the results of research.
- a belief in the fellow humanity of our discourse partners. (As far as I am aware, research in anthropology has demonstrated that there are certain universals in human nature that we must recognize if we are to have respectful discourse when we disagree.)
Now one day we may discover that our rules of logic are not so, and that the notion of "human universals" is mistaken, though I think that unlikely -- but that does not change the fact that our best understanding at present is that they are true and they do work. We have to walk by the best lights that we have.
If you tell me that right now I am typing on a block of cheese and looking into a car engine then I will say, as an absolute, that that is not true, but that I am typing on a keyboard and looking into a monitor.
If you tell me that I am not living in Australia but in Benin then I will tell you, with absolute certainty, that you are mistaken.
There really are things that we know "absolutely". There may be philosophical arguments to dispute that statement. But for everyday purposes and for normal exchanges of ideas we can say that it is an error of logic and therefore invalid to argue in a circle -- to begin with the assumption that X is true that what you want to prove is true. e.g.
The Bible is true because God inspired it.
How do you know God inspired it?
Because the BIble says God inspired it.
That is not a valid argument and I can affirm that it is absolutely invalid. (An absolute)
So where does the problem about objectivity arise?
Our understanding of how the universe works is "true" insofar as our conclusions work, they make sense, we can use them to predict certain things, but they are not absolute unchanging god-ordained Truths. We can expect our understanding of the "laws of the universe" to change as we continue to learn more. The good scientist is one who is constantly aware of that fact (it's an absolute fact for normal everyday discussion purposes) and is therefore open to learning new things about how everything works.
It is the same with historical inquiry. There is always a chance that a new cache of writings will be discovered and what we think we know now will change as a result. How we interpret events will also vary depending on our life experiences and the more we learn. All knowledge is provisional. We never know how we will see things tomorrow. Examples could be listed infinitely.
There is also a chance that we may discover that at some point in our present view of past events we have been -- without recognizing it until now -- using flawed logic. That often happens in any field of inquiry. That's why debate and peer review is a good idea, though sometimes a viewpoint can be so taken for granted even the peer reviewers fail to notice flaws for a time.
And one thing historians learn about their craft is that it is never neutral. No history is neutral -- "purely objective". Every historical inquiry is ultimately a quest to find answers to questions that have relevance to us today, here and now. That's why different generations, different persons from different backgrounds, will often rewrite history.
Re-writing history doesn't necessarily mean denying or changing facts. The facts, the events, remain the same. But sometimes a historian will believe other facts, previously overlooked facts, that have not been included in past historical accounts are relevant to answer certain questions.
Other times a historian might have reasons to believe that a particular fact has been misunderstood or interpreted in a lop-sided way that favour one party over another, and that a "fairer" treatment of that fact would be to explain how other people viewed the event.
Ancient history is as difficult to deal with as modern history. In both fields of research so many sources of information we would like are not available to the researcher. (e.g. I heard that the queen's diaries will not be released until 80 years from now.)
So humility is always a prerequisite for any researcher.
There are indisputable (absolute) facts. I can visit a war cemetery and see the evidence of the dead. But how we interpret them, understand them, feel about them, think about them in the light of other facts we have learned and about our own prejudices --- those will be variables across the panorama of human experience.
If that is disconcerting, think about it this way: if we read another person's viewpoint of "the facts" we are likely to understand that person and the group that that author represents a whole lot better.
History is dead and gone. It does not still exist like some cheshire cat grin for us to photograph and report. All we can do is use our tools of logic and reasoning and human experience, mixed with a measure of self-awareness, to reconstruct events in the most honest way we can. --- and be open to the likelihood that someone else will have a different perspective and see things a bit differently.
That's not undermining society. It's building a more cohesive, respectful and understanding society. The alternative is totalitarian censorship and the history as decided by the elites.
There is much more to write; many caveats to the above; many other questions arising about the nature of history -- but I may have written enough here to at least crack one day a new bit of understanding for someone on the question of "objectivity" in history. But this comment is way too long as it is.
It does not mean that there are no such things as absolutes in our human experience. I like a glass of wine. That' an absolute truth and fact. Too much makes me sick -- that's also an absolute truth and fact that I have learned. Absolutes rule -- but history is an exploration and an adventure in learning -- and a way to understanding ourselves and others. That's also a (potential) absolute.