Full Idea
If someone were to observe beech trees every day over one summer they would have evidence that seems to support both the hypothesis that beech trees are deciduous and the hypothesis that they are evergreens.
Gist of Idea
Several months of observing beech trees supports the deciduous and evergreen hypotheses
Source
Alexander Bird (Philosophy of Science [1998], Intro)
Book Reference
Bird,Alexander: 'Philosophy of Science' [UCL Press 2000], p.20
A Reaction
Bird offers this to anyone who (like me) is tempted to dismiss the 'grue' problem as ridiculous. Obviously he is right; 'deciduous' works like 'grue'. But we invented the predicate 'deciduous' to match an observed property.