Allah, the Lord of all that exists, created everything in pairs. How so? Well, Allah asks us to be mindful, look around, and contemplate. There is darkness, and there is light. Had darkness not existed, light wouldn’t have. There is good vs evil, right vs wrong, and right vs left.
One might say, “Well, there is middle.” Sure, there is, and the opposite of that is extreme. Left vs Right, and Middle vs Extreme.

Moreover, there is birth, and there is death. Then you may argue, “Well, there is life between birth and death.” Yes, you are right, but there is the worldly life and there is the afterlife. Even life itself is made in a pair.
There is, of course, male and female, Y chromosome and X chromosome, estrogen and testosterone.
There is the atom. Then how does an atom have a pair? Well, atoms are made of electrons and protons. They combine to form an atom. But isn’t there a neutron? Neutrons are made of quarks: Up and Down quark, Top and Bottom quark, Strange and Charm quark.
Well, maybe time is not made of atoms, but Allah has created time. However, there is a future and there is a past. Likewise, there is present, and there is absent. What is present in time, but are events that are taking place? And what is absent in time, but are events that are not happening?
Everything is made in pairs. May we be mindful of this duality of nature. The only One who is non-dual is Allah. He is One and has created everything in pairs.