It’s hard to see things through anything but yourself. Which isn’t to say that the world is never as we are but people often forget that they only know their own experience and tend to bend things that way.
I think that I originally saw it in a longer form as “Stephen R. Covey – ‘We see the world, not as it is, but as we are──or, as we are conditioned to see it.'” The general idea gets across, no? Also, can you spot which S is a false one?