Although there appears to be little justification etymologically, there is a useful convention in French whereby the term dualité is reserved for that which is personal, whereas the term dualisme is reserved for that which is not, i.e. for qualities, attributes, and states of mind.
Thus subject-and-object represent a duality, whereas good-and-evil, love-and-hate, represent dualisms.
It may be helpful to follow this convention?
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Personal
Why do I call myself a Buddhist? If it should be necessary to attach oneself to any denomination, and in daily life life there may be circumstances which render that necessary, Buddhism is the only religion which is large enough, in spirit and in practice, to include all the others.