“The humble rarely brag about accomplishments because they are typically significant, and their mannerism is one of confidence; but those with low self-esteem have developed a character of conceit and deception. You’re thinking of one now.”
1982
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“Most people with low self-esteem have earned it.”
Source: Napalm & Silly Putty

“Our self-esteem and conceit are European, but our culture and actions are Asiatic.”
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“Talent is God-given; be humble. Fame is man-given; be thankful. Conceit is self-given; be careful.”
They Call Me Coach (1972)
Variant: Talent is God-given; be humble. Fame is man-given; be thankful. Conceit is self-given; be careful.
The Quotable Sir John