The present studies investigated children's and adults' intuitive beliefs about the physical nature of essences. Adults and children (ranging in age from 6 to 10 years old) were asked to reason about 2 different ways of determining an unknown object's category: taking a tiny internal sample from any part of the object (distributed view of essence) or taking a sample from one specific region (localized view of essence). Results from 3 studies indicated that adults strongly endorsed the distributed view, and children showed a developmental shift from a localized to distributed view with increasing age. These results suggest that even children go beyond mere placeholder notions of essence, committing to conceptual frameworks of how essences might be physically instantiated. (Contains 3 figures and 3 tables.)