definition of c-command and government

Question

Both definitions are from Syntax; A generative introduction (4th edit.)

c-command: Node A c-commands node B if every 'branching' node dominating A also dominates B, and neither A nor B dominate the other.

Q1) What would be wrong or different if we assume that definition of c-command does not include 'branching'?

government: Node A governs node B if A c-commands B and there is no node G such that G is c-commanded by A and G asymmetrically c-commands B.

Q2) What would be wrong or different if we assume that definition of goverment does not include 'G asymmetrically c-commands B'?

Can you explain with some of samples? Thanks!!!

Answer 1

1 matters if your theory requires non-branching nodes. For example, some theories of syntax insist that every phrase have a separate XP and X level (and sometimes also an X' level in the middle), even if their content is exactly the same as the next level down.

If the definition of C-command doesn't include the "branching" stipulation, then "John" doesn't C-command "himself", because "John" is dominated by the NP node and "himself" is not. And one reason to define C-commanding at all is for reflexive pronouns: we say that the "-self" pronouns have to be C-commanded by their antecedents.

2 matters for case assignment, which is one of the original reasons to propose government as a relationship.

We want the object of a verb to become "her", but the subject of an embedded clause to remain "she". So this theory defines government such that "John" governs "himself" in the first example, but does not govern "she" in the second example (the "that" gets in the way). Intuitively, something is governed only by the head that selected it.