August Weismann

"The struggle for existence holds as much in the future as it has held in the past."

"Natural selection is the only true guiding force in the development of organic life."

"Acquired characteristics cannot be inherited; only those traits present in the germ cells pass to offspring."

"Evolution is not a theory of chance, but of necessity."

"The continuity of the germ-plasm is the key to understanding heredity."

"Adaptation is the supreme achievement of nature."

"Life perpetuates itself through an unbroken chain of descent."

"Every organism is a masterpiece of evolution's craftsmanship."

"The study of nature reveals the profound wisdom of creation."

"Competition drives all living things toward perfection."

"Weakness must yield to strength in the natural order."

"The individual lives and dies, but life itself is eternal."

"Heredity is the fundamental law of life."

"Only through understanding nature can we understand ourselves."

"The survival of the fittest is not cruelty but necessity."

"Every variation in nature serves a purpose in the struggle for existence."

"The body is merely the vehicle for the immortal germ-plasm."

"Truth lies in the observation of nature, not in speculation."

"Life seeks always to improve itself through selection and adaptation."

"The complexity of life emerges from simple principles applied over vast time."

"Nature wastes nothing; every structure has been refined by necessity."

"We are not the masters of nature, but its humble students."

"The history of life is written in the structure of organisms."

"Mutation provides the raw material upon which selection acts."

"No individual is greater than the species to which it belongs."

"The preservation of favorable variations is the key to understanding life."

"Nature operates with perfect economy and precision."

"Evolution explains the origin of all living things without exception."

"The struggle for existence is the engine of all progress."

"Life is a continuous battle for resources and survival."