  We point out an earlier unnoticed implication of quantum
indistinguishability, namely, a property which we call `dualism' that
characterizes the entanglement of two identical particles (say, two ions of the
same species) -- a feature which is absent in the entanglement of two
non-identical particles (say, two ions of different species). A crucial
application of this property is that it can be used to test quantum
indistinguishability without bringing the relevant particles together, thereby
avoiding the effects of mutual interaction. This is in contrast to the existing
tests of quantum indistinguishability. Such a scheme, being independent of the
nature and strength of mutual interactions of the identical particles involved,
has potential applications, including the probing of the transition from
quantum indistinguishability to classical distinguishability.
