Say you have 2 keepers (Love and War for example), and the current rules allow you to play 2 cards. In your hand you have All you Need is Love (goal) and Trash a Keeper (action).
Can you trash your own War keeper, play the appropriate goal, and win? Trash a Keeper says you can trash any keeper; to me that includes your own.
Similar situations include when the goal is already played, and various configurations involving Peace (no War) and The Brain (no TV).
This came up in my hand in a game with my daughter the other night, I house-ruled against myself and she went on to win.