Quotation:

 Isaac Newton quotes (English Mathematician and Physicist, "father of the modern science", 1642-1727)

 Galileo Galilei quotes (Italian natural Philosopher, Astronomer and Mathematician who made fundamental contributions to the development of the scientific method and to the sciences of motion, astronomy and strength of materials. 1564-1642)

 Albert Einstein quotes (German born American Physicist who developed the special and general theories of relativity. Nobel Prize for Physics in 1921. 1879-1955)

 Samuel Smiles quotes (Scottish author, 1812-1904)

 Isaac Newton quotes (English Mathematician and Physicist, "father of the modern science", 1642-1727)

 Galileo Galilei quotes (Italian natural Philosopher, Astronomer and Mathematician who made fundamental contributions to the development of the scientific method and to the sciences of motion, astronomy and strength of materials. 1564-1642)

 Isaac Newton quotes (English Mathematician and Physicist, "father of the modern science", 1642-1727)

 Ira Erwin quotes

 kentfrese

 Isaac Newton quotes (English Mathematician and Physicist, "father of the modern science", 1642-1727)

 Edward O. Wilson quotes

 Albert Einstein quotes (German born American Physicist who developed the special and general theories of relativity. Nobel Prize for Physics in 1921. 1879-1955)