Inconsistent triad

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An inconsistent triad consists of three propositions of which at most two can be true. For example:

1. Alice loves me.
2. Alice sends flowers to people she loves.
3. Alice has not sent me flowers.

If one finds oneself believing all three propositions of an inconsistent triad, then (in order to be rational) one must give up or modify at least one of those beliefs. Maybe Alice doesn't love me, or maybe she wouldn't send flowers to me if she did, or maybe she actually has sent flowers.

Any inconsistent triad {A, B, C} gives rise to a trilemma {{A, B}, {B, C}, {C, A}}.