Galileo galilei was a famous italian physicist, astronomer and philosopher who made significant contributions to the sciences of motion, astronomy and to the development of the scientific method. He is best known for improving the telescope to gain better knowledge of the planets and stars. I have never met a man so ignorant that I couldn't learn something from him. 
The less people know and understand about them, the more positively they attempt to argue concerning them, while on the other hand to know and understand a multitude of things renders men cautious in passing judgment upon anything new. 