The release history of this track is a little confusing, but I think it goes something like this: the exact same recording is available on a 45 by Willie Small on Jessica, as well as by Curtis Smith on Doma. The Jessica 45 credits Curtis Smith as writer and producer, but Willie Small as the artist. To make matters worse there is a 45 on Essica (yes, Essica, not Jessica) with a label that says it's Say You Will by Curtis Smith, but which is actually a track called How High Can You Fly. How High Can You Fly also appears on the flip of the Jessica (not Essica) 45, so it's generally considered to be a Willie Small track. The flip of the Essica (not Jessica) 45 is The Living End, credited to Curtis Smith.
Anyway ... whoever it's by it's an excellent little tune, with lazy horns, nice rhythm guitar, great piano and drums, and Curtis' / Willie's pleading tenor.