You can only judge that which is different from this.
Easy targets include ethnicity, religious belief, identity decisions, and profession.
Behind ethnicity is a human heart that enjoys delicious food and flinches at the sight of an incoming punch (and might punch back).
Behind religious belief is a witness looking for a feeling of greater connection.
Behind identity is a being looking for truth.
Behind profession is somebody trying to get by.
No matter your particular definition, I'm guessing you can easily relate to all of these things.
Even understanding requires us to "see behind the wall." To take a split second to realize there is a lot more to the world — particularly people — than meets the eye. Take it as some kind of symbol that only 4% of the known universe is visible in the form of stars, planets, and galaxies. The other 96% is invisible.
Where then to place our focus? On the tiny, tip of the iceberg that you can see? Or the depths far below?
Of course, that is your choice. Limited understanding by nature is limiting however, and there is plenty of it to go around these days.
Even understanding doesn't discredit surface differences—not at all. Surface differences give life spice and variety, otherwise it would get a bit boring around here. But how, truly, can you judge turmeric superior to ginger, when both serve a nearly identical purpose?
Even understanding says that we are this and that, at the same time. We are the ocean, and we are the ocean drop. And if you are, so is everybody else.
That is love.