> First, what is a tree? It’s a big long-lived self-supporting plant with leaves and wood.
Hmm. This is a circular definition. You need to invoke tree to define leaves and wood.
Hmm. This is a circular definition. You need to invoke tree to define leaves and wood.
Lots of plants have leaves. A few don't, some primitive because they hadn't evolved them yet (e.g. algae) and a few because they lost them (broom, cacti). If there were no trees and nobody had ever seen a tree you could still explain leaves.
Lots of plants have wood. Things that aren't trees have wood. They're called bushes. Wood is a thing separate from trees. Not all trees have wood: bananas grow on really big herbs that people call trees because they are tree-sized, but they're herbs. Palm trees aren't really made of wood.
I don't think so?
All non-tree plants have leaves (almost all maybe? edit: not cacti, so not all but most). Wood can be defined biologically ("cellulose fibers embedded in a lignin matrix" or something like that)
EDIT: you could also have totally separate definitions on what wood and leaves are without talking about trees or plants, don't you think?
People who have only seen non tree plants doesn't exist.
And nor does any non tree plant leaves help you generate a tree leaf.