  We indicate the tentative source of instability in the two-dimensional black
hole background. There are relevant operators among the tachyon and the higher
level vertex operators in the conformal field theory. Connection of this
instability with Hawking radiation is not obvious. The situation is somewhat
analogous to fields in the background of a negative mass Euclidean
Schwarzschild solution (in four dimensions). Speculation is made about decay of
the Minkowski black hole into finite temperature flat space.
