Paul Ehrlich

Corpora non agunt nisi fixata.

We must learn to shoot with 'magic bullets'—substances which aim exclusively at the enemy, without harming the body.

The side-chain theory is an attempt to explain the processes of immunity by chemical means.

The body is a complex chemical factory.

The goal of chemotherapy is to find substances that are toxic to parasites but harmless to the host.

The future of medicine lies in chemotherapy.

We need to find substances that are 'parasitotropic' but not 'organotropic'.

The problem of chemotherapy is a problem of differential toxicity.

The ideal drug would be a 'therapia sterilisans magna' – a single dose that cures.

The more we know about the chemistry of life, the better we can combat disease.

Science is a continuous struggle against the unknown.

The greatest joy of a scientist is to discover something new.

Patience and perseverance are essential for scientific discovery.

The path to knowledge is often long and arduous.

We must not be afraid to challenge established ideas.

The human body is a marvel of complexity.

Every disease has a chemical basis.

The immune system is a highly sophisticated defense mechanism.

The development of new drugs requires a deep understanding of biochemistry.

The future of medicine depends on interdisciplinary collaboration.