  Conceptual blending is a powerful tool for computational creativity where,
for example, the properties of two harmonic spaces may be combined in a
consistent manner to produce a novel harmonic space. However, deciding about
the importance of property features in the input spaces and evaluating the
results of conceptual blending is a nontrivial task. In the specific case of
musical harmony, defining the salient features of chord transitions and
evaluating invented harmonic spaces requires deep musicological background
knowledge. In this paper, we propose a creative tool that helps musicologists
to evaluate and to enhance harmonic innovation. This tool allows a music expert
to specify arguments over given transition properties. These arguments are then
considered by the system when defining combinations of features in an
idiom-blending process. A music expert can assess whether the new harmonic
idiom makes musicological sense and re-adjust the arguments (selection of
features) to explore alternative blends that can potentially produce better
harmonic spaces. We conclude with a discussion of future work that would
further automate the harmonisation process.
