Relationships. Symbols are the attempt of the subconscious to interact with the conscious.
Its the attempt at unity of force and form.
It's not necessarily purely emotional, its the tendency for opposites to "attraction" or better yet to seek that which is not "known".
Or the very passion towards completion and creation of something new.
But also that emotion felt during the interaction of the relationship is somewhat of a binding force.
Or a signal or what is yet to come.
The "form" of the relationship is both supported by and created by the "emotion" or heart.
Practically speaking, you can contemplate your life and look at the relationships that have benefited you and consider you emotional state.
And of course analyze those relationships that have not benefited you and the emotions associated with them.
This helps build a conceptual framework for observance.
Emotion is a precursor to action, from my experience, in the framework of personal relationships.
But don't focus on the strongest emotion, consider the patterns of interaction and emotion.
This helps in achieving a more broader perception on things in general.
The Individual Is Paramount
As Within So Without