“Only an ignorant person does not know the difference between criticism and humiliation. All attempts to demean, hurt, and put down with sarcasm, harsh words, curses, and mockery that deny manners and politeness. All actions that provoke anger, irritation and cause hurt feelings are not a form of criticism but humiliation.”
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Open letter to US President Donald Trump (2018)
Context: A good leader tries to embody the best qualities of his or her organization. A good leader sets the example for others to follow. A good leader always puts the welfare of others before himself or herself.
Your leadership, however, has shown little of these qualities. Through your actions, you have embarrassed us in the eyes of our children, humiliated us on the world stage and, worst of all, divided us as a nation.
If you think for a moment that your McCarthy-era tactics will suppress the voices of criticism, you are sadly mistaken.

“The best of ideas is hurt by uncritical acceptance and thrives on critical examination.”
Source: How to Solve It (1945), p. 100