After reading Eric MacDonald’s piece on natural law theory over at Choice in Dying, I think it best to describe how a Critical Rationalist as influenced by Popper and Bartley crosses the ‘is-ought’ gap. Natural law theory seeks to ground ethics in something tangible, something that is easy to grasp. It is in the nature of things to be so, and therefore it follows that we must follow the nature of things. Of course, this indubitably begs the question of what exactly is the nature of things. To take a poor example, it is in the nature of things that bananas fit hands, but bananas also fit into orifices other than the mouth. But put this problem aside for the moment. Assume that it can be solved, or at least a group of people may come to an agreement, tentative though it may be, on the nature of things. Hume, though, notes that it is difficult to justify an ‘ought’ as logically following from an ‘is’, and does not rule this out as impossible. I, on the other hand, take this justification as impossible, since this problem of justification is little more than a variation of Fries’s trilemma: (1) either this ethical justification goes in a circle, (2) grounded on a foundation that is assumed without argument, or (3) part of an infinite series of justifications.
How then can this problem be solved? It may be possible to take the solution for problems in epistemology found in Comprehensively Critical Rationalism and apply it to problems in ethics. While observation statements do not justify scientific theories, if accepted, they delineate which set of theories are logically compatible with them. After adopting heuristics that have survived criticism, we then limit the remaining set even further. For ethics, we may take the nature of things not as justifying ethical programs, but limiting what ethical programs are available for consideration. For instance, if one were to consider the Trolley problem, at its heart is the assumption that scientific theories, especially those that relate to the domain of the human-sized, that attempt to explain the natural world are true. We can take these assumptions, along with a multitude of others, as ‘the nature of things’. If an ethical program should violate any of these assumptions, it is not a viable candidate any longer, unless the group decides that this assumption no longer can withstand criticism.
For instance, if an ethical program dictates that we can warn the lone worker while simultaneously switch the track to the lone worker’s track, we are violating a noncontroversial theory: we cannot be in two places at once.
Or if, for instance, we were to do nothing and the train would turn into a flock of doves, we know that while this is statistically possible, albeit highly improbable, it would be mistaken to perform such an action (or the choice to refrain from acting) under the assumption that the natural world will produce a miracle in order to solve the ethical dilemma. In much the same commonsensical vein, we assume that if we leave an apple on a desk that is injected with a poison, we do not also assume that if anyone should pick up the apple and take a bite, the poison would not be negated by their natural body chemistry, or negated by the antidote they conveniently drank that morning, and so on.
Or, to go one step further, if we think that our actions in the here-and-now do not matter, since the human race is doomed to eternal torment in a lake of fire or destined for an eternal paradise with our loved ones after we die, or that we are not responsible for our choice, for it is a god’s will that one should die and five should live, these theories about the natural world contradict what we take to be the facts or shift the blame onto a supposed entity that is inscrutable and therefore immune to any criticism (other than the very fact that it is immune, not subject to discussion other than on a higher plane of discussion).
We now have an idea of what kinds of theories are impermissible: those that are contradictory, that contradict the facts, expect too much from the state of affairs, posit a solution that trivializes the human condition, immune to criticism, and so on. Once these kinds of ethical programs are removed from the conversation, even though this may be temporary, whatever programs remain can then be addressed by whatever criteria is agreed upon: Does it agree with our intuitions, maximize utility, satisfy a Kantian ideal? Perhaps all three, along with other criteria, are necessary. Perhaps Parfit is correct, and all three are ‘climbing the mountain’ from different starting-points, and will each produce outcomes that are in line with the other two. But that is a discussion for another day. Here then we have a solution to the is-ought problem as seen by a Critical Rationalist: the facts do not entail, justify, make certain or more probable any single ethical program. Instead, the facts limit the possible from the impossible, the serious from the non-serious, and those worthy of our consideration from flights of fancy.