  Here we report the recovery of the binary underlying the classical nova of 11
March 1437 A.D. whose age is independently confirmed by proper motion-dating,
and show that in the 20th century it exhibits dwarf nova eruptions. The four
oldest recovered classical novae are now all dwarf novae. Taken together they
strongly suggest that mass transfer rates decrease by an order of magnitude or
more in the centuries after a classical nova event, greatly slowing the
evolution, and lengthening the lifetimes of these explosive binary stars.
