Louis Pasteur

"Never stop believing in what you cannot yet see."

"Medicine heals doubts as well as diseases."

"The important thing is not so much to know, as to know what you know and what you do not."

"Science is a wonderful thing because it is alive, always growing, always changing."

"Life is the manifestation of force."

"Kind words are short and easy to speak, but their echoes are truly endless."

"The future belongs to those who prepare for it."

"Nature does not proceed by leaps."

"Microbes are marvelous in their simplicity and their complexity."

"To understand the present, we must know the past."

"Vaccination is the most precise application of the germ theory."

"The greatest battles are won in the laboratory."

"Silent gratitude isn't much use to anyone."

"In the world, there is only one real tragedy - not to become a saint."

"Every disease has a specific cause."

"The passion for research is a noble one."

"I have not discovered anything. I have only observed what has always been there."

"Truth is the only beauty that survives time."

"The earth will continue to evolve without us."

"Strength comes from persistence and hard work."

"Let the fear of a single disease drive you to understand all diseases."

"The greatest human achievement is understanding the universe."

"Friendship is a sheltering tree."

"Hope is waiting for what has not yet come to pass."

"Beauty is truth that is perfectly expressed."

"The pen is mightier than the sword, but the microscope is mightier than the pen."

"Knowledge without practice is like a tree without fruit."

"Let your life be a prayer."

"The most important thing is to understand what you are doing."

"Justice is the foundation of all virtue."