I believe that a man can only be useful to his country when he can look at it clearly. — Adam Michnik
It isn’t useful to curse the darkness; instead light your candle and let your light shine. — Hafsat Abiola
An error is more useful than truth: truth is a thought suffering from arteriosclerosis. — Yevgeny Zamyatin
If your selfish goal will be useful to humanity, then let your selfish goal be triumphant! — Mehmet Murat Ildan