“I AM DIFFERENT,” PARACELSUS wrote. “Let this not upset you.”

But it did. He was denounced as a fanatic or impostor and reviled as a drunkard. He was forced to wander from city to city in search of work and bread. He was considered coarse and vulgar, but replied characteristically that “I am a rough man born in a rough country, and what seems silk in my eyes may be but homespun to you.” This was the man who, according to his latest biographer, “started a medical revolution and founded a chemical tradition”.

The “rough country” was Switzerland, but he made all Europe his province. The year of his birth, 1493, can plausibly be seen as the beginning of the modern era. It might be described as the birth of the scientific era, but the word would have meant nothing to him. The term “scientist” was not coined until the 1830s. For Paracelsus and his contemporaries, magic, alchemy and astrology were absolutely embedded within natural philosophy and experimental procedure. Newton was an alchemist and numerologist who drew up arcane recipes for the transmutation of gold and dreamed of rebuilding the Temple of Solomon. Paracelsus predates him by 150 years, but the two philosophers shared the same vital mingling of experimental and transcendental, observed and occult.

Paracelsus first found that confluence in metallurgy. As a child he moved with his father to a mining area of Switzerland, where he became acquainted with the commercial and practical, as well as the spiritual, value of metals. By learning how to separate silver and lead, the early technicians practised alchemy as well as chemistry. It is perhaps significant that other European visionaries, such as Boehme and Swedenborg, were associated with miners and with mining. Luther was the son of a copper smelter. Paracelsus became enamoured of the things beneath the earth.

At the age of 14, in 1507, he became a wandering scholar, moving from university to university in search of enlightenment. He studied medicine but was gorged with a diet of Aristotle and Galen that never satisfied him. He said that “at all the German schools you cannot learn as much as at the Frankfurt fair”. So he pursued the truth in his own way. To become a physician in this period, book-learning was believed to be enough. It was considered injurious to touch a patient and that unfortunate intimacy was left to the “empiric” or surgeon who often doubled as hangman. The true doctor might predict the best day for an operation, or study a patient’s urine, but that was all. “All they could do,” Paracelsus said, “was gaze at piss.”

Paracelsus became a military surgeon for the troops of Spain before continuing his wanderings in search of medical knowledge. “If a man wishes to recognise many diseases,” he said, “let him travel.” He was in Scandinavia. He was in Ireland. He was in Africa. He questioned alchemists, wise women, astrologers and bath-keepers. He came to understand that local diseases might have local cures. He dwelled with the Tartars, and was initiated into shamanism. He visited Venice where he learnt the Kaballah and lingered in Alexandria where he was imbued with the ancient lore of the Egyptians.

He was intent upon practicing natural rather than demonic magic, but still he was accused of having intercourse with demons and of practising divination. He was considered a remnant of the old race of Celtic Druids. He was associated with Dr Faustus and Simon Magus. Yet this did not harm his reputation as a worker of wonders and of miracle cures. He found favour as a court physician among the various princedoms of Europe, but he also earned his bread as an itinerant doctor whose reputation always preceded him.

He was a preacher as well, customarily addressing large audiences in taverns. He despised the religious controversies of the day — he described the Pope and Luther as “two whores debating chastity” — and promulgated a curious mixture of pantheism and neo-platonism. He taught that “man is a sun and a moon and a heaven filled with stars; the world is a man and the light of the sun and the stars is his body”. He also taught that “the human body is vapour materialised by sunshine mixed with the life of the stars”.

He believed that his medicine was efficacious because it was inspired by divine vision. It did have practical benefits. In one of his many volumes, Archidoxa, he emphasised the power of natural remedies. He declared that “all nature is like one single apothecary’s shop”. He was the first to prepare the narcotic diethyl ether, and apparently the first to use laudanum. He wrote what Philip Ball describes as “the first textbook of biochemistry” and, to use another modern term, was the founder and chief defender of “holistic” medicine. He believed that medicines create the conditions for the body to heal itself. As he said, the gardener does not make the seed grow.

Paracelsus had a reputation for drunkenness and gluttony, but that did not inhibit what Ball calls the “adulation” that surrounded him. As a result he made many enemies among doctors, apothecaries and university professors; he spread discord wherever he went. He was called “the Luther of physicians” and provoked fury and contempt; he found himself exiled from many of the cities in which he tried to settle. But he enjoyed controversy. He courted it. He published inflammatory pamphlets and lectures. He abused those who criticised him.

In his last years he became a wayward and unpredictable healer, honoured in one place, reviled in another. It is even possible that, after a lifetime of weary controversy, he succumbed to madness; certainly he began to doubt his own wisdom. He continued writing and publishing, but had become prematurely aged.

“The snow of my misery has come,” he wrote to a friend. “Summer is over.” He died in Salzburg, before he had reached 50. It is said that he requested his body to be buried in excrement, so that it might be renewed by fermentation. But his life was renewed in a different sense. By the turn of the 16th century, as Philip Ball suggests, “ ‘Paracelsianism’ was in the ascendant”. Pilgrims visited his tomb centuries after his death; at a time of cholera, in 1830, crowds flocked to the churchyard in which he lay. This biography is a study of a culture as well as of a man, and in analysing the life and thought of Paracelsus, Ball brings to light a largely forgotten phase of human understanding. It is a considerable achievement.

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