Create a list of undefined user vars?

[DrD]

In [HOME], can a list of undefined variables somehow be created (for later use)?

Example:
dogs:=0; cats:=0; // define vars first
L1:={'dogs', 'cats'};

This works: INPUT({dogs, cats});

This doesn't work: INPUT(L1); // even though L1 ==> {dogs, cats} same as above. (Why not?)

-Dale-