The recently-advanced hypothesis of reopening the way for the dignity of the person by radically neutralising sexual difference and, therefore, the understanding between man and woman, is not right. Instead of counteracting the negative interpretations of sexual difference, which mortify its irreducible value for human dignity, it seeks in effect to cancel out such difference, proposing techniques and practices that make it irrelevant for the development of the person and for human relationships. But the utopia of the “neutral” removes both the human dignity of the sexually different constitution, and the personal quality of the generative transmission of life. The biological and psychical manipulation of sexual difference, which biomedical technology allows us to perceive as completely available to free choice – which it is not! – thus risks dismantling the source of energy that nurtures the alliance between man and woman and which renders it creative and fruitful.