At the age of twenty young Metchnikoff, son of an impoverished Russian aristocrat, had already written important scientific papers and was teaching students older than himself. Ill health, overwork, the tragic death of his young wife and the unrest and repression within Tsarist Russia combined to drive him to the brink of nervous collapse and near suicide; but a happy second marriage and an appointment to the Pasteur Institute in Paris ended the painful years of loneliness and wandering.

In the decades that followed, Metchnikoff established the sciences of cellular embryology and gerontology,  examining life from its first stages to its last. After bitter debate, he proved his theory of phagocytes, the blood cells that protect the body. Not even world acclaim nor a Nobel Prize in 1908 for his immunity theory could distract him from his ceaseless attacks on such killers as tuberculosis, syphilis, typhoid fever and cholera. Even when final victory eluded him, his brilliant pioneering made possible the success of others in his field.

The world is indebted to this great Nobel Prize winner, who overcame all handicaps in his struggle to advance human knowledge and conquer disease.

From the dust jacket