“Too many people believe in what they perceive in others as bad, and completely forget to look in the mirror.”
Related quotes

“That's the real trouble with the world, too many people grow up. They forget.”
From Walt Disney World: Then, Now, & Forever: Too many people grow up. That's the real trouble with the world, too many people grow up. They forget. They don't remember what it's like to be 12 years old. They patronize, they treat children as inferiors. Well, I won't do that. I won't do that. I'll temper a story, yes. But I won't play down, and I won't patronize.
The Quotable Walt Disney (2001)
Context: That's the real trouble with the world, too many people grow up. They forget. They don't remember what it's like to be twelve years old. They patronize; they treat children as inferiors. I won't do that. I'll temper a story, yes. But I won't play down, and I won't patronize.

“The world is as neutral as a mirror. We perceive in it only what we put before it.”

“It is the peculiar quality of a fool to perceive the faults of others and to forget his own.”

“If I looked as good as Justin Chamo Spear I would look in the mirror too”
The Heathen Chinee (1870)

1930s, Speech to the Democratic National Convention (1936)
Context: For too many of us the political equality we once had won was meaningless in the face of economic inequality. A small group had concentrated into their own hands an almost complete control over other people's property, other people's money, other people's labor — other people's lives. For too many of us life was no longer free; liberty no longer real; men could no longer follow the pursuit of happiness.
Against economic tyranny such as this, the American citizen could appeal only to the organized power of government. The collapse of 1929 showed up the despotism for what it was. The election of 1932 was the people's mandate to end it. Under that mandate it is being ended.

"Wordsworth in the Tropics" in Do What You Will (1929)
Source: Do What You Will: Twelve Essays
Context: Too much consistency is as bad for the mind as it is for the body. Consistency is contrary to nature, contrary to life. The only completely consistent people are the dead. Consistent intellectualism and spirituality may be socially valuable, up to a point; but they make, gradually, for individual death.