def relation_set_has_contradictions(relations: Set[str]) -> bool:
    """Return if the set of BEL relations contains a contradiction."""
    has_increases = any(relation in CAUSAL_INCREASE_RELATIONS for relation in relations)
    has_decreases = any(relation in CAUSAL_DECREASE_RELATIONS for relation in relations)
    has_cnc = any(relation == CAUSES_NO_CHANGE for relation in relations)
    return 1 < sum([has_cnc, has_decreases, has_increases])