In the perusal of those early writers [35], he was struck with the profoundest veneration of the simplicity and purity of their doctrines, the holiness of their lives, and the sanctity of the discipline practised by them; but, as he descended to the lower ages, found the peace of Christianity broken by useless controversies, and its doctrines sophisticated by the subtilties of the schools:  he found the holy writers interpreted according to the notions of philosophers, and the chimeras of metaphysicians adopted as articles of faith:  he found difficulties raised by niceties, and fomented to bitterness and rancour:  he saw the simplicity of the christian doctrine corrupted by the private fancies of particular parties, while each adhered to its own philosophy, and orthodoxy was confined to the sect in power.

Having now exhausted his fortune in the pursuit of his studies, he found the necessity of applying to some profession, that, without engrossing all his time, might enable him to support himself; and having obtained a very uncommon knowledge of the mathematicks, he read lectures in those sciences to a select number of young gentlemen in the university.

At length, his propension to the study of physick grew too violent to be resisted; and, though he still intended to make divinity the great employment of his life, he could not deny himself the satisfaction of spending some time upon the medical writers, for the perusal of which he was so well qualified by his acquaintance with the mathematicks and philosophy.

But this science corresponded so much with his natural genius, that he could not forbear making that his business, which he intended only as his diversion; and still growing more eager, as he advanced further, he at length determined wholly to master that profession, and to take his degree in physick, before he engaged in the duties of the ministry.

It is, I believe, a very just observation, that men’s ambition is, generally, proportioned to their capacity.  Providence seldom sends any into the world with an inclination to attempt great things, who have not abilities, likewise, to perform them.  To have formed the design of gaining a complete knowledge of medicine, by way of digression from theological studies, would have been little less than madness in most men, and would have only exposed them to ridicule and contempt.  But Boerhaave was one of those mighty geniuses, to whom scarce any thing appears impossible, and who think nothing worthy of their efforts, but what appears insurmountable to common understandings.

He began this new course of study by a diligent perusal of Vesalius, Bartholine, and Fallopius; and, to acquaint himself more fully with the structure of bodies, was a constant attendant upon Nuck’s publick dissections in the theatre, and himself very accurately inspected the bodies of different animals.

Having furnished himself with this preparatory knowledge, he began to read the ancient physicians, in the order of time, pursuing his inquiries downwards, from Hippocrates through all the Greek and Latin writers.