William Harvey Explains The Circulatory System

Some of the most inspiring achievements in history have been accomplished not on battlefields or corridors of courtly power, but by the patient persistence and steady resolve of learned men. Masculine energy is best expressed in focused effort, breaking through barriers, and bursting through boundaries. The slow amassing of expertise in a field, the careful collection of data, the intense study of such data, and the sudden flash of inspiration that can move mountains and change the paradigm: is there any drama more compelling?

One such example is the discovery of the circulation of the blood by William Harvey in the seventeenth century. Although we take anatomical knowledge today for granted, it is important to remind ourselves that this knowledge took centuries to acquire; and each step forward was made by men guided by persistence, intuition, and hard labor.


After his education at Cambridge and then Italy, Harvey returned to England to practice medicine in London. He secured appointment as personal physician to James I and Charles I. Like Vesalius—whom I have discussed previously here at Return of Kings—he carried out laborious and painstaking examination of cadavers to wean himself away from reliance on Galen, who for two thousand years had held the medical profession in his grip.

A great genius in his time, Galen’s texts had begun to show their age by the early seventeenth century. Galen had believed that the liver, as well as the heart, helped to convey blood throughout the body, and confused the proper function of the veins, arteries, and the heart’s septum and ventricles. Physicians before Harvey had cast doubt on Galen’s theories:  Vesalius and Fabrizio had showed, by careful study, that the veins and arteries could not function as Galen believed. In the 1550s, Servetus and Realdo Colombo had discovered the pulmonary circulation of the blood.

And here we see another characteristic feature of a great man: the ability to build on the work of those who came before him, without slavishly adhering to the theories of predecessors. Even great men like Harvey have to stand on the shoulders of those who came before: rarely in science is discovery accomplished in a total vacuum. Harvey’s forebearers made major steps forward, but what was needed was one man to tie it all together in a comprehensive explanation of how the blood circulated throughout the body.

What I find interesting about scientific discoveries is the process of how the discoverer begins his journey. Harvey made the chance observation that the amount of blood expelled from the heart by each contraction was about half an ounce. It followed, then, that in an hour the heart should pump into the blood vessels over 1000 ounces. But this was a larger amount of fluid than the body contained. Clearly, the blood in the body was not being continuously generated by the tissues, but was being circulated to and from the heart by some continuous cycle of ingress and egress.  But how, precisely, was this happening?  No one could answer this question.

Obsessed with this problem, his exhaustive experimentation finally demonstrated that venous blood (blood carried by the veins) was being carried toward the heart, and that arterial blood was being carried away from it. He imagined the motion of the blood throughout the body as “a motion as it were in a circle.” For its day, such an assertion was revolutionary. It directly contradicted Galen and the legacy of medieval medicine.  Islamic medicine, far ahead of Europe in the Middle Ages, had conspicuously missed this fact as well. Harvey arrived at his theory by 1615, but hesitated to publish it straight away.

His book Anatomical Explanation of the Action of the Heart and Blood in Animals found print in Frankfurt, Germany in 1628. It probably seemed safer to Harvey to release his bombshell on continental Europe first, rather than in his backyard in England. It has been called “the first and greatest classic of English medicine.” He predicted no one would believe him, and he was right. The publication of the work temporarily blackened his reputation, and he found his medical practice suffer grievously. However, like so many theories which are ahead of their time, Harvey’s explanation of the circulation of the blood was confirmed beyond doubt by another physician in 1660, who demonstrated how capillaries carry blood from the arteries to the veins.  It was a moment of vindication and triumph.


Like many men of great ability, he found it difficult to hold his tongue and suffer fools. He was brusque, prickly, and curt to those he deemed unworthy of his patience; but this was the defense mechanism of a man who had been mocked and ridiculed by lesser intellects for years. He was what he had to be. His pugnacity earned him many enemies, but he found in Charles I a loyal advocate.

He continued to work and discover well into his old age. In a treatise published in 1651, he attacked the commonly-held view of the “spontaneous generation” of animals, and postulated that all animals ultimately evolved from eggs. It is a view held by biologists today. He had the true scholar’s humility and awe of the physical universe. “All that we know”, he said, “is still infinitely less than all that remains unknown.”

Although William Harvey may seem a minor figure today, greater appreciation of his achievement is realized when we recall that in his day the only tools available to a physician were his eyes, hands, and surgical instruments that had hardly changed since antiquity. The human body, as Vesalius showed, is a complex and mysterious machine. How all the parts worked together was not at all obvious. It is one thing to map and describe the internal organs, as Vesalius did, but quite another to demonstrate by experimentation precisely how these organs operate. And is there anything more inspiring than the sight of a great man incrementally and patiently working towards that noblest of goals, the advancement of learning?

Read More:  The Greatest Physician In History

25 thoughts on “William Harvey Explains The Circulatory System”

  1. Its like SOOO the patriarchys fault that it wasnt a woman who discovered this. This article is so misogynist !

  2. Never heard of this guy before. There’s so much you miss.
    Giordano Bruno is another figure of the time that’s quite interesting. He may have been the first to postulate that extra-solar planets existed, an insight that was so far ahead of its time that even astronomers in the 80’s were laughing at the people looking for them, now of course astronomers think that most stars probably have planets. I want to know how he arrived at such conclusions.

      1. He was. He also traveled to a lot of different countries in his career. When he was in England he was a spy serving under Elizabeth I’s spymaster Francis Walsingham.
        He led a pretty interesting life.

    1. Ironically, exoplanets before the 1990’s qualified as a woo-woo belief according to skeptics’ own standards. People believed in their existence any way as a faith position because science fiction propagandized the culture with the idea.
      Consider the original Star Trek, for example. A scientifically parsimonious version of that show, based on the astronomical evidence in the 1960’s, would have Captain Kirk and his crew travelling to plain, no-planet stars.

  3. In return, I present the market for lemons, which is pertinent to women and life:
    A used car is one in which ownership is transferred from one person to another, after a period of use by its first owner and its inevitable wear and tear. There
    are good used cars (“cherries”) and defective used cars (“lemons”),
    normally as a consequence of several not-always-traceable variables,
    such as the owner’s driving style, quality and frequency of maintenance,
    and accident history. Because many important mechanical parts and other
    elements are hidden from view and not easily accessible for inspection,
    the buyer of a car does not know beforehand whether it is a cherry or a
    lemon. So the buyer’s best guess for a given car is that the car is of
    average quality; accordingly, he/she will be willing to pay for it only
    the price of a car of known average quality. This means that the owner
    of a carefully maintained, never-abused, good used car will be unable to
    get a high enough price to make selling that car worthwhile.
    Therefore, owners of good cars will not place their cars on the used
    car market. The withdrawal of good cars reduces the average quality of
    cars on the market, causing buyers to revise downward their expectations
    for any given car. This, in turn, motivates the owners of moderately
    good cars not to sell, and so on. The result is that a market in which
    there is asymmetric information with respect to quality shows characteristics similar to those described by Gresham’s Law:the bad drives out the good. (Although Gresham’s Law applies more specifically to exchange rates, modified analogies can be drawn.)

    1. And what does this have to do with the price of tea in China, pyjama boy? Or the article about Harvey?

      1. Dude loves hearing himself talk. Who else here writes a novel in the comment section on every article?

  4. A brief history of humanity:

    In ancient times before Christ, the Pharisees (lawmakers) of
    the time had invented debt-based currency and a code of laws for all to follow.
    Christ was the first real competition they had and the first real political
    revolutionary. So this ‘Synagogue of Satan’ killed him. In time, they had
    poisoned all religions, including Christianity, with truth mixed in with lies.
    They could not hide Christ’s existence, so they sought to sully his teachings,
    and deceive others’.
    By the 330AD, Constantinople was founded, alongside ‘Roman
    Catholicism’, which became a proxy for a new re-imagined Roman Empire. This new
    Christianity had false teachings mixed in with truth. The capitol was moved
    from Rome to its new site, with a further 1/3 move left to put the capitol where
    it was really wanted by the ‘elite’ of that time. In Jerusalem. But all roads
    lead to Rome, and the Roman empire collapsed as the trade routes to
    Constantinople were not favourable.
    Over the next century and a bit, many wars were fought in
    the subverted Christianity’s name. The Muslim religion was founded by the elite
    as an antidote to Christianity.
    By the late 1700s, the House of Rothschilds had beaten
    Napoleon and gained control of all of Britain through financial manipulation.
    They established a mighty empire, with the Satanic aim of re-establishing the
    third temple at Jerusalem, where Constantine had failed. They financed both
    sides of all wars and continue to do this in the present day, having staged the
    Ukraine anti-government ‘revolution’.
    The UK is the financial power. The Vatican is the political
    seat, where the last Pope (Petrus Romanus = Peter of the Roman/US empire) is
    bringing in ecumenical teachings, into the Church, which arguably goes against
    Christianity. Lastly, the US is the military arm, and has been used in the last
    few decades to establish dictatorships in various nations, with the excuse
    being given to the general public that ‘a world police’ is needed.
    We are now in the end-game. We all know the bankers are the
    hidden hand that controls society, for none of the big names were prosecuted
    following the financial crisis. We can see/feel something is wrong. Kissinger
    had recently suggested that ‘Israel will cease to exist in 10 years’. The
    Iraelis are actually Edomites from the Caucausus, and are being used to
    establish the third temple from which the fabled Antichrist will rule. The real
    Israelites are spread all over the world, with only a handful in Israel. In any
    case, we will see scripture be fulfilled at some point in the next few decades,
    but the cost in terms of human suffering will be immense. People of all races
    and creeds will suffer and fight, at the beckoning of the Satanists, who see
    themselves as the true rulers of the human race and as benevolent people.
    Truth is hard to find in the modern era, but this researched
    account is as close to the truth as we will get.

    1. Go and read Marcus Aurelius’s diary. Christianity really fucked up Rome. They were radicals that ended up turning Rome on itself. There were other issues, but Christianity didn’t help Rome one bit.

    2. By the way, all banking is based on debt. Debt is just based on credit, faith, and trust. Trying to blame debt is just plain stupid. You may wanna lay down your conspiracy theories and actually bother to use reason and logic. All religions today are fucked up and distorted–it’s not just Christianity.
      By the way, Constantine fucked up Rome. He was not a good emperor by any means. He just continued to turn Rome on itself. All of the largest empires in the world where based in either secular thought or some form of paganism (ex. Persia, Rome at its peak, Mongol Empire, American “empire” right now). By the way, the US was not founded as a Christian nation.
      “As the Government of the United States of America is not, in any sense, founded on the Christian religion,—as it has in itself no character of enmity against the laws, religion, or tranquility, of Mussulmen [Muslims],—and as the said States never entered into any war or act of hostility against any Mahometan [Mohammedan] nation, it is declared by the parties that no pretext arising from religious opinions shall ever produce an interruption of the harmony existing between the two countries.”–Treaty of Tripoli
      This was signed by President John Adams, who was a very devout Christian and ratified by Congress.

      1. I would actually say that banking, in general, is based on fraud. That’s a banker saying that.
        There is debt and then there is finance. Debt is what the average person has. Finance is what the mega-rich (or the string-pullers, if you will) have. Taxes pay the costs of finance. The government-banking system is how elites pay for their wars and their lifestyles. Or more accurately, how you and I pay for it.

        1. But finance is the single most important part of a country’s development. Personally, I think at least 50% of a country’s development is finance. If you do not have development in finance, you will not have the development of an economy.
          But yes, bankers do take control over the system for their advantage to the detriment of the system as a whole though.

  5. Thanks for another excellent article, Quintus. Inspired to keep learning and sharing.

  6. “It probably seemed safer to Harvey to release his bombshell on continental Europe first”.
    The Continent was deemed safer because of L’affaire Galilee. Galileo was another interesting character from the Early Modern Age. Not as a discoverer per se, but more of a effectively bold salesman. As shrewd as Edison, and as scandalous as Tesla.

  7. Great reading Quintus.
    ‘rarely in science is discovery accomplished in a total vacuum’.
    This is a very important observation.Indeed ,I would be curious to know of a counter example: a discovery accomplished in total vacuum,so to speak.I would NOT consider serendipitous discoveries to exemplify (like Flemming’s discovery of Penicillin).
    Every science advancement comes from standing on the shoulder of Giants.
    Darwin from Malthus,Einstein from Maxwell (among others).Indeed not just pertaining to science but all others as well.For example Gandhi’s ideas non-violence came for Tolstoy.

    1. I’m not sure if Babbage and his calculating machine was an original idea. His idea about what we call the binary system-on/off, yes/no etc may have been original.

      1. Babbage was inspired by card-programmable devices like the Jaquard loom. And all of his computing engines were decimal, not binary; the first binary-logic computer (that we know of) was that of Konrad Zuse, the German engineer.
        Southern Man

        1. Yes but binary pre-dated Babbage. I meant whose idea it was but wasn’t sure if he ever made any sort of computer. Wasn’t the idea from Leibniz? Some people say it’s from Chinese or African but there’s no proof unless I’m wrong here.

    1. You don’t understand. It was about animals being offspring of others of their type and not just coming out of nowhere. Spontaneous generation used to be a common belief where say for example maggots would arise on dead flesh but people didn’t make the connection that they came from eggs or fly larvae and were genetic offspring of the fly.

        1. of course the egg came first, and don’t mistake this for a chicken egg but see it as a type of cell. Which in the long term continued to evolve into more complex constallations.

  8. I’ve noticed that articles like this one get very few comments.That’s because the pyjama boys here are really only interested in how to pick up girls.They want to hear about if you do A,B and C etc you will have girls throwing themselves at you.They call this learning game lol Game of course is just a lot of bullshit and snake oil that they have deluded themselves into believing in their sex starved state is some sort of “science” and theory.Hmm if I only had game then I’d be able to pick up girls just like the Alpha big boys.It never occurs to them that faking something rather than being the genuine article is easily detected by the female because reproduction is the most important thing in life for them.
    When you point out the game is really just some pick up scheme they’ll try to change “game” into something like it’s really just trying to improve yourself. It’s just a rationalisation on their part because all of these self improvement ideas always seem to come back to the primary reason they do them which is picking up girls.For example, “working out” is not just about being fit to them but to build muscles because they believe this is going to attract females.The same is true about learning things like style etc things that they should have just been developing as they grew up. They’re not doing these things for their own sake and where it just comes natural to them and is part of them but because some game “guru” told them they can get girls doing this.Without the female pickup angle they’d be out of shape poor slobs if left to their own device.

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