His name is Paracelsus (Theophrastus Bombastus von Hohenheim), physician and alchemist, amond others. If you're not the common Hollywood or internet meme grown person, you probably know that, unlike Don, Paracelsus was a Renaissance real person whose activity changed Western science on the long term. Many writings of his survived, although few are mainstream or even translated into different languages.

Exerpts from some biography on him:
1902encyclopedia:

...the epithet Paracelsus, like some similar compounds, was probably one of his own making, and was meant to denote his superiority to Celsus.
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Doubtless Paracelsus learned rapidly what was put before him, but he seems at a comparatively early age to have questioned the value of what he was expected to acquire, and to have soon struck out ways for himself.
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So he left school chemistry as he had forsaken university culture, and started for the mines in Tyrol owned by the wealthy family of the Fuggers. The sort of knowledge he got there pleased him much more. There at least he was in contact with reality. The struggle with nature before the precious metals could be made of use impressed upon observation.
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he had proof hat positive knowledge of nature was not to be got in schools and universities, but only by going to Nature herself, and to those who were constantly engaged with her. Hence came Paracelsus’s peculiar mode of study. He attached no value to mere scholarship; scholastic disputations he utterly ignored and despised,—and especially the discussions on medical topics, which turned more upon theories and definitions than upon actual practice.

[here I insert a quote from one of his works about this Nature, as, in his opinion, the only authority in teaching the absolute truth, thing that he insisted on - he often put critiques against the established medical cliques in his very works:
O, you hypocrites, who despise the truths taught you by a true physician, who is himself instructed by Nature, and is a son of God himself! Come, then, and listen, impostors who prevail only by the authority of your high positions!
]
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For the physician it is ten times more necessary and useful to know the powers of the heavens and the earth, the virtues of plants and minerals, than to spend his time on Greek and Latin grammar. And the commentary of his own and succeeding centuries upon these very extreme views is that Paracelsus was no scholar, but an ignorant vagabond. He himself, however, valued his method and his knowledge very differently, and argued that he knew what his predecessors were ignorant of, because (1) he had been taught in no human school.
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He had-acquired great stores of facts, which it was impossible for him to have reduced to order, but which gave him an unquestionable superiority to his contemporaries. So in 1526 or 1527, on his return to Basel, he was appointed town physician, and shortly afterwards he gave a course of lectures on medicine in the university. Unfortunately for him, the lectures broke away from tradition. They were in German, not in Latin; they were expositions of his own experience, of his own views, of his own methods of curing, adapted to the diseases that afflicted the Germans in the year 1527, and they were not commentaries on the text of Galen or Avicenna. Unfortunately they attacked, not only these great authorities, but the German graduates who followed them and disputed about them in 1527. They criticized in no measured terms the current medicine of the time, and exposed the practical ignorance, the pomposity, and the greed of those who practiced it.
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Paracelsus had burst upon the schools with such novel views and methods, with such irresistible criticism, that all opposition was at first crushed flat. Gradully the sea began to rise. His enemies watched for ships and failures; the physicians maintained that he had no degree, and insisted that he should give proof of his qualifications. His manner of life was brought up against him. It was insinuated that he was a profane, that he was a conqurer, a necromancer, that, in fact, he was to be got rid of any cost as a troubler of the peace and of the time-honoured traditions of the medical corporations. Moreover, he had a pharmaceutical system of his own which did not harmonize with the commercial arrangements of the apothecaries, and he not only did not use up their drugs like the Galenists, but, in the exercise of his functions as town physicians, urged the authorities to keep a sharp eye on the purity of their wares, upon their knowledge of their art, and upon their transactions with their friends the physicians.
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He bases it on the general relationship which man bears to nature as a whole: he cannot divorce the life of man from that of the universe; he cannot think of disease otherwise than as a phase of life. He is compelled therefore to rest his medical practice upon general theories of the present state of things; his medical system—if there is such a thing—is an adaptation of his cosmogony.
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His eagerness to understand the relationship of man to the universe led him to the Kabbala, where these mysteries seemed to be explained, and from these unsubstantial materials he constructed, so far as it can be understood, his visionary philosophy. Interwoven with it, however, were the results of his own personal experience and work in natural history and chemical pharmacy and practical medicine, unfettered by any speculative generalizations, and so shrewd an observer as Paracelsus was must have often felt that his philosophy and his experience did not agree with one another. It was doubtless a very great ideal of medicine which Paracelsus raised; but when it came to realizing it in every-day life he could hardly do else than fail.
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He had besides arrived by some kind of intuition at the conclusion that the operations in the body were of a chemical character, and that when disordered they were to be put right by counter operations of the same kind.
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Probably therefore his positive services are to be summed up in this wide application of chemical ideas to pharmacy and therapeutics; his indirect and possibly greater services are to be found in the stimulus, the revolutionary stimulus, of his ideas about method and general theory. It is not difficult, however, to criticize Paracelsus and to represent him as so far below the level of his time as to be utterly contemptible. It is difficult, but perhaps not impossible, to raise Paracelsus to a place among the great spirits of mankind. It is most difficult of all to ascertain what his true character really was, to appreciate aright this man of fervid imagination, of powerful and persistent convictions, of unbated honesty and love of truth, of keen insight into the errors (as he thoughts them) of his time, of a merciless will to lay bare these errors and to reform the abuses to which they gave rise, who in an instant offends us by his boasting, his grossness, his want of self-respect. It is a problem how to reconcile his ignorance, his weakness, his superstition, his crude notions, his erroneous observations, his ridiculous inferences and theories, with his grasp of method, his lofty of the true scope of medicine, his lucid statements, his incisive and epigrammatic criticisms of men and motives.