Accordingly, it follows from the first paragraph that the signs belong to the same element or different, but complementary to each other. As you know, there are only 4 elements — Fire, Earth, Air and Water. That is, within each element, the signs are compatible with each other and the pairs representing a positive combination of the elements Fire-Air and Earth-Water are compatible.
The signs of the elements of Fire and Air are odd, and the signs of Earth and Water are even. Therefore, the compatibility of the signs of each pair of elements, both among themselves and inside, is very natural: Air helps the Fire to flare up more, and Water fills the Earth, making it fertile.
On the other hand, in combinations of signs of different parity - these are pairs of elements Water-Fire, Water-Air, Earth-Fire, Earth-Air - there is no positive union. Moreover, even from the nature of the elements, it is clear that some of these pairs are opposing. Therefore, their compatibility in love and family is considered negative.
This is how compatibility of zodiac signs works in general at the compatible/incompatible level.

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