Who said "I have lived long enough to understand human nature"?

This quote is attributed to Justice Wargrave.

I have lived long enough to understand human nature - Justice Wargrave

"I have lived long enough to understand human nature"

Justice Wargrave Wisdom

Character in And Then There Were None

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"Murder is justified when the victim deserves it."

"The guilty cannot hide forever."

"Justice must be served."

"Every man and woman is alone."

"I'm not angry, I'm just disappointed."

"The best things in life are free."

"You can't have everything in life, but you can have what matters most."

"A woman's intuition is rarely wrong."