  We explore a possibility to generate exotic hadrons dynamically in the
scattering of hadrons. The s-wave scattering amplitude of an arbitrary hadron
with the Nambu-Goldstone boson is constructed so as to satisfy the unitarity
condition and the chiral low energy theorem. We find that the chiral
interaction for the exotic channels is in most cases repulsive, and that the
strength of the possible attractive interaction is uniquely determined. We show
that the attractive interaction in exotic channels is not strong enough to
generate a bound state, while the interaction in nonexotic channel generate
bound states which are considered to be the origin of some resonances observed
in nature.
