What are the differences in meaning and usage between “voice-leading”, “part-writing”, “polyphony” and “counterpoint”?
According to Wikipedia:
- Voice-leading is “the term used to describe the linear progression of melodic lines (voices) and their interaction with one another to create harmonies, according to the principles of common-practice harmony and counterpoint.”.
- Part-writing redirects to Voice-leading, yet there it says that “Voice leading practices can be codified into rules for pedagogical purposes. In these settings, ‘voice leading’ is often synonymous with ‘part writing,’ …” — that suggests that it is not always synonymous!
- Counterpoint is “the relationship between voices that are harmonically interdependent (polyphony) yet independent in rhythm and contour.”
- Polyphony is a “musical texture … that consists of two or more simultaneous lines of independent melody”.
The currently accepted answer to another question clarifies that counterpoint is polyphony obeying certain rules, so the main issue is how “voice-leading” and “part-writing” fit in. A summary in one place of how all four terms are used, in different contexts if necessary, would be helpful.