For James Mill, the individual maintains some command over sensations (i.e. in a controlled environment) as they derive from sensible objects. However, one cannot recall ideas or trains of ideas at will, Mill pointed out: “Thoughts come into the mind unbidden.” But ideas can be linked with sensible objects, such as sounds, smells, sights, and so on. Language thus provides signs, e.g. audible and visible, which mark sensations and recall ideas (Mill 1829a, I.86–89). This way knowledge acquired from the past can be used to guide the future. For example, certain words recall certain ideas and trains of ideas. These ideas or trains of ideas, with or without additional links, might lead to certain behavioral responses, e.g. thoughts, emotions, actions. Analyses of chains of associations identify the links between elicited responses (last step) and actual experience (first step). This is almost impossible to do in cases of indissoluble association, as sensations, ideas and trains of ideas are fused together indiscriminately. Hence, even though most children associate darkness with ghosts, Mill offered an example, “[i]n some this association is soon dissolved,” in others “it continues for life,” especially come the night (Mill 1829a, I.60, 286–87). Even a mind like Bentham’s had failed to dissolve such an association.