Paul Ehrlich

To cure syphilis is to free humanity from a ancient curse.

Magic bullets.

We must learn to shoot with 'magic bullets' which strike only the harmful invaders and spare the healthy cells.

The side-chain theory of immunity.

The cell is a chemical individual.

The problem of chemotherapy is to find substances which possess a specific affinity for the parasite and a minimal affinity for the host.

The organism is a mosaic of different cells, each with its own specific chemical properties.

The goal of chemotherapy is to find substances which are highly toxic for the parasite but harmless for the host.

The ideal drug would be a 'magic bullet' that would seek out and destroy only the disease-causing organisms without harming the patient.

The side-chain theory offers a comprehensive explanation for the phenomena of immunity.

The cell possesses specific receptors, or 'side-chains', which are capable of combining with various substances.

The combination of a toxin with a cell is a chemical process.

The production of antitoxins is a compensatory process, where the cell overproduces its side-chains in response to toxin binding.

The specificity of immune reactions is due to the specific configuration of the side-chains.

The development of chemotherapy is based on the principle of selective toxicity.

The search for specific remedies against infectious diseases.

The organism is a chemical system.

The cell is the fundamental unit of life, and its chemical properties determine its function.

The future of medicine lies in the development of specific chemical agents.

The problem of immunity is essentially a chemical problem.