**Contact**: If you have any questions and comments, please contact Vishal Sunil Arvindam (vsunilar@ucsc.edu)
**Short Abstract**
We employ the visual world paradigm to probe negation using simple declarative sentences. First, we asked whether 2-year-olds understand the truth-functional meaning of “not.” Second, we explored the stages of negation processing. Specifically, we asked whether children in the early stages of negation processing (a) first compute the representation of the affirmative counterpart before interpreting negation, or (b) incrementally map negation onto the unfolding sentence representation from its occurrence. We provide preliminary evidence that 2-year-olds not only understand the truth-functional meaning of “not” but also immediately engage in this computation within 1500 ms of its occurrence.