The supreme court is like a baseball team in the respect that there are NINE members.
One of the ballplayers is the Captain (think Chief Justice).
Now, if four players quit the team (and one of those happens to be the captain) then you're left with four replacements to be made. During the process of bringing the team up to full strength (NINE) the Manager (President) names one of his NINE players the new "captain". The "captain" may be one of the original nine or one of the FOUR new players. Either way, there's no way to slip a tenth player onto the field.
Please stay off the appropriations committee, Congressman! ;-)