The idea of an objective reality has been under attack for a while, and I have even been part of the team attacking that objective reality. We know that we have a limited ability to sense and experience the world around us. We know that bats, sharks, and bees experience phenomena that we are blind to. We can’t know that the color red that I experience is exactly like the color red that you experience. Given our lack of sense, the fact that physical stimuli are translated into electrical brain impulses, and that there appears to be plenty of subjectivity in how we experience the same thing, an objective reality doesn’t really seem possible. We seemingly all live within a world created by many subjective measures within our own brains.
But is this idea really accurate? I recently completed Steven Pinker’s book Enlightenment Now in which he argues that reason depends on objectivity and that our efforts toward rationality and reason demonstrate that there is some form of objectivity toward which we are continually working. The very act of attempting to think rationally about our world and how we understand the universe demonstrates that we are striving to understand some sort of objective commonality. A quote from The Book of Why by Judea Pearl seems to support Pinker’s assertion. Pearl writes:
“We experience the same world and share the same mental model of its causal structure. … Our shared mental models bind us together into communities. We can therefore judge closeness not by some metaphysical notion of similarity but by how much we must take apart and perturb our shared model before it satisfies a given hypothetical condition that is contrary to fact.”
Pearl wrote this paragraph while discussing the human ability to imagine alternative possibilities (specifically writing about the sentence Joe’s headache would have gone away if he had taken aspirin). The sentence acknowledges a reality (Joe has a headache) and proposes a different reality that doesn’t actually exist (Joe no longer has a headache because he took aspirin). It is this ability to envision different worlds which forms the basis of our causal interpretations of the world, but it also reveals a shared world in which we live and from which we can imagine different possible worlds. It hints at an objective reality shared among individuals and distinct from unreal and imagined, plausible worlds.
Reason and rationality demonstrate that there seems to be an objective reality in which we are situated and in which we experience the world. There are undoubtedly subjective aspects of that world, but we nevertheless are able to share a world in which we can imagine other possible worlds and consider those alternative worlds as closer or further from the world in which we live. Doing this over and over again, among billions of people, helps us define the actual objective reality which constitutes the world we share and from which we have subjective experiences. It is from this world that we can discuss what is subjective, what causes one phenomenon or another, and from which we can imagine alternative realities based on certain interventions. If there was no objective reality for us to all share, then we would never be able to distinguish alternative worlds and compare them as more or less close to the world we share and exist within.