J.S. Bach, Invention 4

for Species

Cantus firmus
First species
Second species
Third species
Fourth species

The following are guidelines for species counterpoint that I have developed over the years, drawing on various texts as well as my teachers. Needless to say, these are only for reference; they are not intended to be final, nor are they an accurate representation of sixteenth-century style. They are, however, a place to start.

Lawrence Zbikowski, University of Chicago Department of Music

Melodic style sheet for cantus firmus and species


  1. It is best if each line is an integral gesture—a deliberate motion toward, and subsequent recession from, a single climax.
  2. Accidentals outside of the key are not permitted. The only exceptions are minor-key scale degrees six and seven, which may be raised in order to provide a leading tone at the close of an exercise.
  3. The total range of a line should not exceed a tenth.
  4. Notes of the counterpoint may be tied if necessary (as part of oblique motion), but only one tie should appear in an exercise.
  5. Intervals

  6. Acceptable melodic intervals are major and minor seconds, thirds, and sixths, and perfect fourths, fifths, and octaves.
  7. No more than two consecutive leaps are advised; any more and the line loses its melodic sense.
  8. Avoid outlining triads with consecutive thirds.
  9. A dissonant interval (tritone, seventh) should not be outlined by the boundary points of an ascent or descent.
  10. Variety

  11. Unbroken ascents or descents should be limited to at most five notes.
  12. Stepwise motion is generally preferred, but a few well-considered leaps are required for variety.
  13. Leaps larger than a third should be immediately preceded (if applicable) and followed by motion in the opposite direction; in short, step in the opposite direction after a leap.


  14. No note should appear more than three times in a line; high and low points are most effective if they occur only once.
  15. Avoid anything that might be heard as a repeating pattern (e.g., sequence, motive, contour shape).

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Two-part counterpoint rules: First Species


  1. Counterpoints above a cantus firmus begin at the unison, octave, or fifth; those below, at the unison or octave. Endings are always at the unison or octave.
  2. The penultimate simultaneity must be an imperfect consonance (i. e., a third or a sixth). In most cases the penultimate note of the counterpoint will be the leading tone, which must be raised in minor. (Phrygian is the one exception. Even though it is a minor mode, because there is only a half-step between the first and second steps of the scale, the seventh step of the scale is never raised.)
  3. Intervals

  4. First species counterpoint is completely consonant note-against-note counterpoint. Intervals permitted between the counterpoint and cantus firmus are major and minor thirds, sixths, and tenths, and perfect unisons, octaves, and fifths. Fourths are not allowed as harmonic intervals.
  5. The unison may be used only at the beginning and end of an exercise.
  6. Thirds and sixths predominate in exercises, with fifths and octaves thoughtfully deployed for variety.
  7. Parallel and "anti-parallel" perfect intervals are not permitted.
  8. Perfect intervals approached by similar motion ("hidden") must be avoided; they are especially prominent if both voices move by leap.
  9. Chains of more than three consecutive thirds or three consecutive sixths should be avoided.
  10. Avoid a cross relation against the leading tone in minor.
  11. Part-writing

  12. To promote independence of voices, contrary motion is preferred over similar motion or parallel motion, and similar motion is preferred over parallel motion. Oblique motion is acceptable, but introduces a static element into the exercise. No one type of motion should persist to the point of monotony.
  13. It is conducive to independence when the climax of the counterpoint does not coincide with that of the cantus.
  14. Simultaneous leaps in cantus and counterpoint should be avoided.
  15. Voice crossing and/or overlapping must be avoided.

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Two-part counterpoint rules: Second Species


  1. In second species there are two notes to each note of the c.f. (however, see #3 and #4 below). The coincidence of notes of the counterpoint and c.f. creates beats that are strong in comparison to the single notes that occur in the counterpoint, heard as weak beats. The counterpoint will of course be notated in half notes.
  2. The opening and closing intervals are the same as those in first species.
  3. The counterpoint can begin on the beat or off the beat (after a rest).
  4. The counterpoint ends with a whole note (as does the c.f.); the penultimate measure of the counterpoint can be a whole note as well, if desired.
  5. No ties or repeated notes are permitted in the counterpoint.
  6. Intervals

  7. Dissonant intervals are allowed on the second half note of the measure if approached and left by step. According to the rules we are using, both dissonant passing tones and dissonant neighbors are allowed. Beware, however, of the stasis the latter can lead to.
  8. Avoid a leap into an octave from the weak beat of the preceding measure (this can lead to what is called ottava battuta).
  9. Unisons are permitted (sparingly) on the weak beat of the measure.
  10. A distance of a thirteenth is permitted between voices—as always, use discretion.
  11. Voice-leading

  12. From a strong beat to a weak beat only one voice moves (the counterpoint)—this voice is governed by overall melodic writing rules and #6 above.
  13. From a weak beat to a strong beat both voices move—motion is then governed by first species rules.
  14. In general, strong beats should still adhere to first species rules.
  15. It is better to leap within the measure than across the bar line. Indeed, stepping across the bar line is a highly effective way of generating a sense of melodic fluency, especially when it occurs as part of a passing motion (with either a consonant or a dissonant passing note).
  16. Consonant neighbor motions are permitted, but they should be used with care since they can tend to stall the forward movement of the melodic line.

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Two-part counterpoint rules: Third Species


  1. In third species there are four notes to each note of the c.f. (however, see #3 and #4 below). As in second species, the coincidence of notes of the counterpoint and c.f. creates strong beats, now on the first quarter note of each measure.
  2. The opening and closing intervals are the same as those in first species, and the counterpoint will contain no ties and no repeated notes.
  3. The counterpoint may begin on the beat or after a quarter rest (which asserts the independence of the voices).
  4. The counterpoint ends with a whole note; the penultimate measure of the counterpoint will have four quarter notes, the last of which will be scale degree 2 or 7. See example 3-40, p. 68 of Salzer and Schachter, Counterpoint in Composition for sample cadential endings.
  5. Intervals

  6. All first beats are consonant.
  7. Dissonance, strictly controlled as always, is permitted on the remaining quarter notes of the measure. All dissonant notes will be connected stepwise on both sides to other notes of the counterpoint with the exception of the stylized figures covered in #7. Both passing and neighboring motions will result.
  8. Two exceptions to dissonance treatment are
    1. the double neighbor figure
    2. the nota cambiata
  9. Neighbor motions are essentially static; their use should be limited.
  10. Remember, the resolution of a dissonance creates motion in the direction of the resolution; it is always best to follow this direction.
  11. Unisons are permitted on any beat other than the first; use at most one unison per measure.
  12. Voice-leading

  13. Within the measure only one voice moves; this voice is governed by overall melodic writing rules and #6 & #7 above.
  14. From beat 4 to beat 1 both voices move; motion is then governed by first species rules.
  15. Parallel perfect intervals from strong beat to strong beat are possible if treated correctly.
  16. It is better to leap within the measure than across the bar line.

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Two-part counterpoint rules: Fourth Species


  1. The purpose of fourth species counterpoint is to learn to control suspensions (or what were called syncopes in the period). It is thus written in half notes, with as many second beats tied over to first beats as possible; however, see #4 below.
  2. The counterpoint always begins after a half measure of rest (to promote independence of the voices), and ends on a whole note (or breve).
  3. The opening and closing intervals are the same as always.
  4. It is possible to break the succession of tied notes occasionally in order to improve voice leading. The counterpoint then follows second species rules.
  5. Intervals: Suspension Figures

  6. The first note of a tied pair (or syncope) is always consonant.
    1. If the second note (on the strong beat) is consonant, the counterpoint is then governed by second species rules; this is a consonant syncope.
    2. If the second note (on the strong beat) is dissonant, the dissonance must be resolved downward in stepwise motion; this is a dissonant syncope, which we conventionally call a suspension. A syncopated dissonance that resolves upward is called a retardation. This figure was not used in the conservative style associated with species, although there is no particularly good reason why it couldn't be used—it just wasn't.
  7. With counterpoint above the c.f.
    1. 7-6 and 4-3 suspensions may be used liberally; when a series of the same type of suspension is used in succession, this is called a chain of suspensions
    2. 9-8 suspensions can lead to parallel octaves—these may be used only singly (they cannot be used in chains of suspensions)
    3. 2-1 suspensions should be used only in emergencies.
  8. With counterpoint below the c.f.
    1. 2-3 and 9-10 suspensions may be used liberally (they can be used in chains of suspensions)
    2. 4-5 suspensions can lead to parallel fifths—these may be used only singly (they cannot be used in chains of suspensions)
    3. 7-8 suspensions are generally excluded
  9. Avoid repeating the same type of suspension more than three times (break the chain of suspensions after the third instance of a particular type).
  10. Voice-leading

  11. If two unisons, fifths or octaves occur in adjacent measures with only a dissonant suspension in between, the voice leading will be unacceptable. Thus, 9-8 and 4-5 suspensions will not occur in series. On the other hand, 6-5 and 5-6 in series are good, especially the 5-6.
  12. Consecutive perfect intervals on weak beats are permitted.

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Bach, Prelude from Clavier-Buechlein

For inquiries about this page, or suggestions, contact Lawrence Zbikowski, Department of Music, University of Chicago.