Scientific reductionism has made dramatic progress in nearly all areas of study, but it has failed to explain human personal freedom. Most people believe that they are rational beings with the agency to make personal choices in their daily lives.
Science has sometimes shown that personal choices are constrained by non-obvious factors, or are misinformed, or are correlated in unexpected ways. Physics predicts the future by setting up time-dependent differential equations. But ultimately people make decisions that do not feel like just the time evolution of the solution to a differential equation.
A barrier to understanding human decisions is consciousness. People collect data through their senses, and we can analyze that. The data enters the brain, and there is some progress in understanding that. But at some point the data enters into a human conscious awareness of possible choices, and the conscious brain makes a decision on its own. How that happens is a total mystery to science.
There is not even a good definition of consciousness, nor any agreement over whether animals and computers are ever conscious. They certainly do not appear to be conscious in the way that humans are, but without a sharp definition, we cannot say.
Maybe some day there will be artificially intelligent computers that are obviously conscious, and maybe there will be a good understanding of what makes a computer conscious, but maybe not. We are not even sure that other people are fully conscious.
Is Hillary Clinton conscious? She was widely regarded by intellectuals as being the most qualified person for the most important job in the world. Surely a top requirement would be for a fully conscious person who can make good decisions. And yet she also appeared fully programmed and predictable, and there was no way to be sure that she ever made any conscious decisions.
It is not even clear that it makes any sense to have a scientific explanation of freedom. Science is all about reducing observations to deterministic sequences of events. Scientific ideas are demonstrated by doing repeatable experiments.
Freedom is all about not being determined by previous events. Freedom is demonstrated by doing something that no one can predict.
Some people respond to this dilemma by denying that freedom exists. They might say, “I have a rational scientific outlook, and freedom cannot have a scientific explanation, so therefore there is no such thing.”
Or they might argue as follows. There is no god or human soul, so the brain is just a wet computer following the laws of physics. We don’t know how the brain works, but just knowing that it obeys the laws of physics tells us that it is a programmed automaton with no free will of its own because the laws of physics are deterministic.
The laws of physics are not even really deterministic, because of uncertainties from chaos, quantum mechanics, and unknown effects, but that does not faze the people making the anti-freedom argument. Their conception of science and freedom are mutually exclusive, and they would say that freedom is unscientific no matter what the laws of physics are.
Thus explaining freedom is completely intractable. Those who believe in freedom get stuck on the problem of consciousness, and the others get stuck on the problem of scientific repeatability.
Freedom is experienced by everyone who gives a rating to this essay. You can readily find detailed explanations on video display, internet communications, muscle contraction, digital computer processing, electrical power transmission, optics, and everything else related. But when it comes to actually deciding on a rating, science has almost nothing to say.