Explaining language change: A three step process

changes by saying that children sometimes do mistakes and that
they misinterpret information. This can also be seen from the
fact that grammar changes not only take to complex or rare
phenomena, but also those we can assume are rather simple.
Hence we should claim that children must have good reasons
for misinterpreting the information they receive, rather than
saying that they have made mistakes (cf. Guðmundsdóttir
2000). There are two main factors to take into consideration
when studying language acquisition in this connection:
(7) a. Does the language competence of the parents
offer another interpretation of the system?
b. Does language performance fully reflect language
competence?
These questions help us to search for natural explanations for
the misinterpretation that can take place during language
acquisition. Neither inaccuracy, laziness, nor lack of logical
thinking is the reason for the so-called mistakes that the
children do, leading to grammar changes, rather the mistakes
reflect a very logical interpretation of the information the
children receive through language use.
As discussed earlier, children do only have access to the
grammar (I-language) of their parents through their language
performance. Therefore it is natural to expect grammar changes
to take place where there is no obvious connection between
interpretation of the language performance (output) and the
underlying structure. Grammatical phenomena cannot be
acquired correctly unless they are clearly reflected by language
performance. When a certain phenomenon has survived through
many generations, it must have been reflected clearly in the
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