Postmodern philosophy claims that we never see reality as it actually is. The reason for this is because in order to see something we have to think about it. Supposedly, we think in “language.” Language is arbitrarily constructed by society, and contains all the biases of that society. And so anything we think about is molded by the biases of our culture, and thus we never see reality as it actually is.
Just to be clear, I think there’s a small kernel of truth to this, but mostly a lot of hooey.