Horses in Nostromo are almost always symbolic of conquest, such as the
equestrian statue of Charles IV just below. This image virtually equates Charles
with conquest, but in a particularly subtle way. A centaur does not ride a horse,
i.e., he is not directing conquest to a personal aim, he is himself the horse.
This corresponds to material progress as a force for disembodied justice, that
attempts to conquer without ruling. Charles Gould's ambition is to be a
form of conquest rather than a conqueror, and the attempt to sublimate himself
in this way makes him 'half a man' in many regards. But the half that is still
man corresponds to rulership, and we will see that the conquering force of material
progress thrusts upon Charles the mantle of the "King of Sulaco" whether
he likes it or not, finally equating him with Charles IV.