SQL & PL/SQL

When I run the following query, I get no rows back.
However, when I comment out the START WITH, I get the expected 120 rows, including six rows with pred = 1.

select pred, succ from
(
  with q as 
  (
    select 1 as n from dual
    union all select 2 as n from dual
    union all select 3 as n from dual
    union all select 4 as n from dual
    union all select 5 as n from dual
    union all select 6 as n from dual
    union all select 7 as n from dual
  )
  select q1.n AS pred, q2.n AS succ 
  from q q1
  join q q2 on q2.n > q1.n
)
connect by prior succ = pred
start with pred = 1;

Am I missing something obvious?

-- Don