Not everything has a physical opposite, even if we can fabricate one for sake of discussion.
Example: There is "orange", the actual fruit, what one might call orange-rupa, and there is "orange", the concept, the idea, the name, the definition, orange-nama, the pointer I've just used several times now to reference orange-rupa. The two are derived from eachother: orange-rupa is the origin of orange-nama, but orange-nama is the way in which we understand orange-rupa. However, "not-orange" is itself just a concept, a negation of orange, and it has no physical correlate. Orange did not arise from "not-orange". You could use "not-orange" to specify everything orange might've arisen from, in dependence on it, and that would be correct, but then, you're not actually describing anything at all, just playing games with language in a way that's confusing. Hence, the world probably didn't begin with Yin and Yang, Yab-Yum, 3 Gunas, or whatever other grandiose and superstitious simplification.
So, in conclusion, I don't really need to know everything that's "not-orange" to eat an orange. Studying apples -- which are not orange -- tell me much less about oranges than oranges themselves. And in order to experience an orange, I don't even necessarily need a concept for orange at all. Without any preconceptions at all, with mindfulness I can eat an orange and know what it tastes like.
Similarly, without any preconceptions and with mindfulness, you can find happiness and develop compassion.
The best things in life aren't things.