“Philosophical entropy” is the idea that the more ways there are for a person to be wrong, the more people will be wrong. When a multiple-choice question gets fewer right answers as more options are added, that’s one of the simplest forms of philosophical entropy. The existence of multiple differing political ideologies within a population is a more complicated example of philosophical entropy.
I call this concept “philosophical entropy” in quite the literal sense. Entropy is defined as the tendency for a system to occupy all accessible microstates, weighted by the difficulty of accessing each particular microstate. Physically, this means that any system comprised of particles that can each be in two possible microstates of equal energy will have half of its particles in one microstate and half in the other microstate.
If we borrow this concept from physics and apply it to philosophical epistemology, we can think of each belief system as a macroscopic statistical system. Each logical step or choice a person must make in order to construct that belief system is a microstate. Each logical step can either be right or wrong. Once a single incorrect logical step is made, the person’s entire belief system is built on faulty logic, and will be wrong unless they somehow correct that error through another counteracting error later. The more logical steps there are, the more chances a person has to end up wrong. In other words, while travelling down a pathway from axioms to ideological conclusions, the more different branches there are at which a person must choose a direction to travel, the more likely they will eventually choose a wrong path, and end up at the wrong ideological conclusions.
Thus, philosophical entropy suggests that if we assume that there is one right ideology, then the more wrong ideologies there are, the fewer people will be right. Ideological diversity is thus harmful to the ultimate goal of getting more people to be right, unless NOBODY has yet found the right answer.