Sex is uniquely determined by presence or absence of Y chromosome. Clearly, this definition is self explicit. For example 46 XX is FEMALE, due to absence of Y chromosome. Similarly its presence in 46 XY makes it a MALE. But there are 47 XXY, 47 XYY and 47 XXX too, though they are rare. One inviolate rule: No Y, it is female. Then how can SC order a third gender, transgenders? How can you change the gender of a man by castration? It is like saying that SC can decide that Pluto is a planet. Can it? Can SC declare that global warming is man made? Clearly such matters are outside the purview of SC and exclusively within the domain of science.