What are the main differences between a Sentence and a Period? I’m comparing to understand both forms better. I’ve found this explanation:
“Schoenberg applied the term ‘sentence’ to a very specific structural type distinct from the antecedent-consequentperiod. In a sentence’s first part, a statement of a ‘basic motive’ is followed by a ‘complementary repetition’ (e.g. the first, ‘tonic version’, of the shape reappears in a ‘dominant version); in its second part this material is subjected to ‘reduction’ or ‘condensation’ with the intention of bringing the statement to a properly ‘liquidated’ state and cadential conclusion. The sentence was one of a number of basic form-types Schoenberg described through analysis; another was the period. In Schoenberg’s view, ‘the sentence is a higher form of construction than the period. It not only makes a statement of an idea, but at once starts a kind of development’ (Schoenberg 1967, p.58).”
“Macpherson (1930, 25) defines a musical sentence as “the smallest period in a musical composition that can give in any sense the impression of a complete statement.” It “may be defined as a period containing two or more phrases, and most frequently ending with some form of perfect cadence.”
So, I’m a bit confused…I think that sometimes a period could be called “sentence” and viceversa (depends on the content). Is that true?
I recommend watching the lessons specifically on the sentence and the period, as I lay out in detail how they are formed.
First, I am pulling my theory from more modern sources. Definitions are primarily from William Caplin’s Classical Form, and Sonata Theory by Hepokoski and Darcy. While Caplin uses a lot of Schoenberg’s thinking as a starting point, he has significantly developed his ideas, and brought much more clarity to the terminology.
The sentence is an 8-measure theme type, with two phrases – a presentation phrase and a continuation phrase. The presentation contains a basic idea and a repetition of the basic idea. The continuation usually contains fragmentation, increase in surface rhythmic activity, harmonic acceleration and a cadence.
This differs from the period in several key ways. The period has an antecedent and a consequent phrase. The antecedent contains a basic idea, and a contrasting idea, that ends in a weak cadence. The consequent contains a basic idea, and another contrasting idea that ends in a strong cadence. Weak cadence in this case could be a half-cadence (HC), or an imperfect authentic cadence (IAC), and a strong cadence would just have to rhetorically be stronger than the weak, so in the case of an IAC in the antecedent, you would need a PAC. If the weak cadence were a HC, then you could have a IAC or PAC as the strong cadence.
The presentation phrase in a sentence does not end in any sort of cadence. You also don’t have the return of the complete basic idea in the continuation, so they sound different.
While I do like to occasionally read older theory books, their terminology tends to be used haphazardly and usually leads to confusion.
Thanks Jon, I get it. Besides I see that I’ve to re-watch some videos to understand better some concepts. Thanks