Kierkegaard’s only valid form of certain, objective knowledge is in the realm of logic (or its extension of mathematics). Theoretically, approximate objective knowledge can be gained in the realm of history and science, but it’s only ever approximate, so it can’t be said to be “certain,” and is always subject to revision. M.G. Piety details SK’s distinct categories of knowledge in her book Ways of Knowing: Kierkegaard’s Pluralistic Epistemology, and those are the only two realms of objective knowledge she can distinctly identify.
Interestingly, McCombs addresses how this situation has reversed in contemporary culture in The Paradoxical Rationality of Søren Kierkegaard:
Although the Hegelian System is now dead and gone [what Kierkegaard spent much of his time lambasting], systematizing is still alive and well. For example, scientific naturalists claim to know that all reality is material reality, or that all reality is to be known, to the extent that it can be known, not in diverse ways but exclusively by the public methods of mathematical and empirical sciences. (70)
This is an inversion of SK’s notion of what counts as truly objective knowledge — math and logic provide objective knowledge according to Kierkegaard, but they are not the limit of what is knowable. This, in my opinion, is a large reason why we experience a large amount of doubt about any religious or ethical truth claims. We have accepted the cultural claim re: immanence — that we can only know what is provable empirically or logically because we cannot empirically or logically prove anything exists outside of the material world.
Modernism and the Enlightenment have been the favorite whipping boys in theology and philosophy for decades now. The notions of objectivity (especially in the sciences, but also in philosophy) and pure reason are rightfully derided as being fairly untenable in the post-modern age, especially after the turn in philosophy toward language.
Of course, the concern when this is granted is always that without a framework where we affirm that our language and thoughts directly link to reality (i.e., realism), “relativism” – especially moral relativism – abounds. This is essentially the fear that, if we cannot say with confidence that our language matches up to reality, the words we use to describe reality cannot be “true” or “real.” This further leads to the question of whether there even is an objective reality outside of the reality that humans make for themselves. And if so, what is to stop us from creating a reality in which pedophilia, racism, and economic exploitation are not only acceptable but good?
I think these fears tend to be overblown. We only latched onto the notion of the possibility of epistemological objectivity in the West because that’s the story that eventually won the day by the 1700s. We miss the fact that this isn’t the story the rest of the world has told about humanity and knowledge and what we can understand about reality. This Western framework might have given us industrialism and technological explosions and the age of information — but did it make us better? In the rush to be purely rational and gain all knowledge possible, we might have made ourselves more like machines, but did we make ourselves better human beings because of it?
Perhaps accepting our contingency and the fact that we are incapable of purely rational thought, perhaps affirming our social contexts and the subjectivity under which we have been placed, and perhaps understanding that our “knowledge” is bent by the lenses through which we evaluate information and rational argument will allow us to embrace humility and help us adopt a posture of openness to realities other than our own. Perhaps, by embracing “relativism,” we can become better humans and better Christians.