def is_more_sonorous(self, other):
		'''
		compare this phoneme to another for sonority.
		Used for SSP considerations.
		'''
		if isinstance(other, Consonant):
			return True
		elif self[Height] > other[Height]:
			return True
		elif self[Height] == other[Height]:
			return self[Backness] > other[Backness]
		else:
			return False