  Controllable story generation is a challenging task in the field of NLP,
which has attracted increasing research interest in recent years. However, most
existing works generate a whole story conditioned on the appointed keywords or
emotions, ignoring the psychological changes of the protagonist. Inspired by
psychology theories, we introduce global psychological state chains, which
include the needs and emotions of the protagonists, to help a story generation
system create more controllable and well-planned stories. In this paper, we
propose a Psychology-guIded Controllable Story Generation System (PICS) to
generate stories that adhere to the given leading context and desired
psychological state chains for the protagonist. Specifically, psychological
state trackers are employed to memorize the protagonist's local psychological
states to capture their inner temporal relationships. In addition,
psychological state planners are adopted to gain the protagonist's global
psychological states for story planning. Eventually, a psychology controller is
designed to integrate the local and global psychological states into the story
context representation for composing psychology-guided stories. Automatic and
manual evaluations demonstrate that PICS outperforms baselines, and each part
of PICS shows effectiveness for writing stories with more consistent
psychological changes.
