The Supreme Court shall consist of a Chief Justice and six Associate Justices. Five members of the court shall constitute a quorum. When necessary, the Chief Justice shall assign the Judge or Judges of the Superior Court, senior in service, as provided by rules of the Supreme Court, to serve temporarily in the Supreme Court. In case the Chief Justice is absent or unable to serve, a presiding Justice designated in accordance with rules of the Supreme Court shall serve temporarily in his stead.