What
are we trying to explain?
lAlmost
all organisms communicate.
lHowever,
human language biologically unique.
¡Learned through observation without negative evidence,
or reliable feedback
from limited experience.
¡Infinitely
expressive using finite means.
¡Syntactic structure: autonomous system mediating signals
and meanings.
¡Dynamic:
language changes on many timescales.
¡Constrained
cross-linguistic variation. e.g., word-order universals.
¡Mixture
of regular rule-based regularity and
irregularity.