Here we begin to see the problem, as knowledge of a person’s biological sex is neither sufficient nor even necessary for sexual attraction. What Joe finds sexually attractive is a largely culturally conditioned collection of traits, not female-ness in general. After all, Joe is not sexually attracted to every woman he meets, only to those who have the particular collection of traits he finds sexually attractive. Thus a person’s biological sex is not sufficient for sexual attraction. But neither is it necessary, as sexual attraction can be present even before a person’s biological sex is known.