Hello!
Three quotes I like:

"He who knows others is wise;
He who know himself is enlightened."
Lao-tzu, The Way of Lao-tzu, Chinese philosopher (604 BC - 531 BC)

"Daring ideas are like chessmen moved forward. They may be beaten, but they may start a winning game."
Goethe, German writer & polymath (1749 – 1832)

"To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection."
Henri Poincaré, French mathematician, theoretical physicist, and a philosopher of science. (1854 – 1912)

Good luck to all,
Polo.