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Friedrich Hayek with a class at the London School of Economics, 1948

John Stuart Mill may well be the most important liberal thinker of the nineteenth century. In countless respects, his once-revolutionary arguments have become familiar, even part of the conventional wisdom. Certainly this is so for his great 1869 essay The Subjection of Women, which offered a systematic argument for sex equality at a time when the inferior status of women was widely taken for granted. It is also true for On Liberty, published in 1859, which famously argued that unless there is harm to others, people should have the freedom to do as they like. A strong advocate for freedom of speech, Mill offered enduring arguments against censorship. He also had a great deal to say about, and on behalf of, representative government.

Friedrich Hayek was the twentieth century’s greatest critic of socialism, and he won the Nobel Prize in economics. A lifelong defender of individual liberty, he argued that central planning is bound to fail, even if the planners are well motivated, because they cannot possibly assemble the information that is ultimately incorporated in the price system. Hayek described that system as a “marvel,” because it registers the knowledge, the preferences, and the values of countless people. Hayek used this insight as the foundation for a series of works on freedom and liberalism. Committed to free markets and deeply skeptical of the idea of “social justice,” he is a far more polarizing figure than Mill, beloved on the political right but regarded with ambivalence by many others. Nonetheless, Hayek belongs on any list of the most important liberal thinkers of the twentieth century.

Mill and Hayek help to define the liberal tradition, but in both temperament and orientation, they could not be further apart. Mill was a progressive, a social reformer, an optimist about change, in some ways a radical. He believed that, properly understood, liberalism calls for significant revisions in the existing economic order, which he saw as palpably unjust: “The most powerful of all the determining circumstances is birth. The great majority are what they were born to be.” Hayek was not exactly a conservative—in fact he was sharply critical of conservatism on the ground that it was largely oppositional and did not offer an affirmative position—but he generally venerated traditions and long-standing practices, seeing them as embodying the views and knowledge of countless people over long periods. Hayek admired Edmund Burke, who attacked the idea that self-styled reformers, equipped with an abstract theory, should feel free to override social practices that had stood the test of time. Mill had an abstract theory, one based on a conception of liberty from both government and oppressive social customs, and he thought that society could be evaluated by reference to it.

Against this background, there is every reason to be intrigued by a new book with the title Hayek on Mill. Hayek died in 1992, but the University of Chicago Press is continuing with a multivolume edition of his collected works. Readers are discovering essays by Hayek that were never published, were not easily available, or were not widely known. What would Hayek have to say about a great champion of liberty, in some ways his intellectual ancestor, who ended up embracing socialism?

How stunning, then, to find that the volume has only a few snippets on that question. Instead it largely consists of a book, first published in 1951, that grew out of an enormous, uncharacteristic, and somewhat obsessive undertaking by Hayek, which was to assemble what remains of the correspondence between Mill and his eventual wife, Harriet Taylor (one or the other destroyed numerous letters, probably including the most interesting), and to use it as the basis for a narrative account of their mysterious love affair.

The book raises mysteries of its own. For all his greatness, Hayek was a cold, abstract, and distant writer, celebrating the operations of free markets but without a lot of interest in the full range of human emotions. Some liberals (including Mill) have a romantic streak; Hayek is not among them. How was it, exactly, that Hayek, of all people, became captivated by the story of John Stuart Mill and Harriet Taylor? A possible answer is that he had to explain to himself and others why Mill—one of the few thinkers he had to regard as an intellectual equal or superior—moved away from what Hayek celebrated as classical liberalism, which for Hayek was focused on limited government and protection of free markets. But Hayek’s interest in the romance itself outpaced his interest in the evolution of Mill’s thinking (perhaps because of the beauty and great delicacy of the correspondence).

Does that romance have anything to do with liberalism and liberty? I think so. One of the lessons we can draw from Hayek’s work of excavation is that Mill’s distinctive form of liberalism, with its emphasis on individual freedom from the confining effect of social norms, had a great deal to do with his relationship with Taylor. As we shall see, Hayek himself missed the connection entirely, because his own preoccupations lay elsewhere.


Hayek begins the book with one of his central puzzles, and it involves Taylor rather than Mill: “The literary portrait which in the Autobiography John Stuart Mill has drawn for us of the woman who ultimately became his wife creates a strong wish to know more about her.” Mill’s own account suggests that she must have been “one of the most remarkable women who ever lived.” Hayek quotes a very long passage from Mill himself:

In general spiritual characteristics, as well as in temperament and organization, I have often compared her, as she was at this time, to Shelley: but in thought and intellect, Shelley, so far as his powers were developed in his short life, was but a child compared with what she ultimately became. Alike in the highest regions of speculation and in the smaller practical concerns of daily life, her mind was the same perfect instrument, piercing to the very heart and marrow of the matter; always seizing the essential idea or principle.

The same exactness and rapidity of operation, pervading as it did her sensitive as [well as] her mental faculties, would with her gifts of feeling and imagination have fitted her to be a consummate artist, as her fiery and tender soul and her vigourous eloquence would certainly have made her a great orator, and her profound knowledge of human nature and discernment and sagacity in practical life, would in [the] times when such a carrière was open to women, have made her eminent among the rulers of mankind.

Mill had a lot more to say about Harriet Taylor:

Were I [but] capable of interpreting to the world one half the great thoughts and noble feelings which are buried in her grave, I should be the medium of a greater benefit to it, than is ever likely to arise from anything that I can write, unprompted and unassisted by her all but unrivalled wisdom.

One of Hayek’s projects is to discover whether Mill’s account was “sheer delusion.”

Mill and Taylor met at a dinner in 1830, when she was just twenty-two, a mother of two boys, and married for four years to John Taylor, eleven years older than she and a junior partner in a family firm of wholesale druggists. Thomas Carlyle called him “an innocent dull good man.” An acquaintance describes her, at the time, as “possessed of a beauty and grace quite unique of their kind,” with “large dark eyes, not soft or sleepy, but with a look of quiet command in them.” She wrote poetry and was soon to produce a number of essays on social usages and conventions, including one that prefigured Mill’s attacks on conformity, decades later, in On Liberty.

For his part, Mill was nothing like the dry, somewhat desiccated old man depicted in photographs. Twenty-four at the time, he must have cut a dashing figure, having been described by Carlyle as “a slender, rather tall and elegant youth,” who was “remarkably gifted with precision of utterance, enthusiastic, yet lucid, calm.” At the same time, his emotional state was not good. In a forlorn letter to a friend, written a year before meeting Taylor, he referred to “the comparative loneliness of my probable future lot,” and contended that there was “now no human being…who acknowledges a common object with me.”

In his autobiography, Mill insisted that it was not until years after meeting Taylor that their relationship “became at all intimate or confidential.” Hardly. Referring to an article published in mid-1831, Taylor’s closest friend pointedly wrote her, “Did you or Mill do it?” In the same year, a letter from a mutual friend, written to John Taylor, spoke mysteriously of the need for a “reconciliation” between Mr. Taylor and Mill. In 1832, Mrs. Taylor wrote Mill that they must not meet again, to which Mill responded in French: “Sa route et la mienne sont séparées, elle l’a dit: mais elles peuvent, elles doivent, se rencontrer. A quelqu’ époque, dans quelqu’ endroit, que ce puisse être, elle me trouvera toujours ce que j’ai été, ce que je suis encore.” (Her path and mine are separate, she said so: but they can, they must, come together. At whatever time, in whatever place that might be, she will find me forever as I was, as I am still.) A few weeks later, their relationship resumed.

By 1832, the two had embarked on some kind of love affair. Taylor wrote Mill: “Far from being unhappy or even low this morning, I feel as tho’ you had never loved me half so well as last night.” And later, in response to an apparent confession from Mill:


I am glad that you have said it—I am happy that you have—no one with any fineness & beauty of character but must feel compelled to say all, to the being they really love, or rather with any permanent reservation it is not love—while there is reservation, however little of it, the love is just so much imperfect…. Yes—these circumstances do require greater strength than any other—the greatest—that which you have, & which if you had not I should never have loved you, I should not love you now.

The Taylors agreed to a separation, and Mill and Harriet were able to spend time together. To a close friend, Mill wrote a rapturous letter:

I am astonished when I think how much has been restrained, how much untold, unshewn and uncommunicated till now…. Not a day has passed without removing some real & serious obstacle to happiness…. There will never again I believe be any obstacle to our being together entirely.

Taylor wrote in a similar spirit, stating that “there has been so much more pain than I thought I was capable of, but also O how much more happiness.”


National Portrait Gallery, London

John Stuart Mill and Harriet Taylor; paintings by George Frederic Watts, 1873, and an unknown artist, circa 1834

Hayek writes that in the middle of the 1830s, Mill and Taylor did not try to conceal their intimacy but, confronted with a great deal of malicious gossip, they withdrew almost entirely from social life. In 1834, Carlyle wrote of the rumor that Mill had “fallen desperately in love with some young philosophic beauty” and been “lost to all his friends and to himself.” Enraged by the gossip, Mill cut off a number of his friendships. He wrote to a friend: “What ought to be so much easier to me than to her, is in reality more difficult—costs harder struggle—to part company with the opinion of the world, and with my former mode of doing good in it.”

It is not entirely clear what happened between Mill and Taylor from the middle 1830s to the late 1840s. What little that remains of their correspondence shows a degree of agitation within and between them. Taylor to Mill: “I don’t know why I was so low when you went this morning. I was so low—I could not bear your going my darling one; yet I should be well enough accustomed to it by now.” The two were alert to the reactions of others; Mill seemed especially sensitive on that count. Taylor to Mill, perhaps teasingly: “I was not quite wrong in thinking you feared opinions.—I never supposed you dreaded the opinions of fools but only of those who are otherwise wise & good but have not your opinions about Moralities.” But there can be little doubt about the intensity of their relationship. Taylor to Mill: “When I think that I shall not hold your hand until Tuesday the time is so long & my hand so useless. Adieu my delight.”

In 1848, Taylor returned to London after traveling with Mill, only to discover that her husband had fallen gravely ill with cancer. For a period of two months, she dedicated herself entirely to caring for him and saw Mill not at all, restricting herself to correspondence, some of it angry, even bitter:

You talk of my writing to you ‘at some odd time when a change of subject of thought may be rather a relief than otherwise’! odd time! Indeed you must be ignorant profoundly of all that friendship or anxiety means when you can use such pitiful narrow hearted expressions.

And as her husband neared the end: “The sadness & horror of Nature’s daily doings exceed a million fold all the attempts of Poets! There is nothing on earth I would not do for him & there is nothing on earth which can be done. Do not write.”

In 1851, two years after her husband’s death, she and Mill were married. The event must have been joyful, a kind of completion, but as Hayek reports, “the marriage led to the most painful episode in Mill’s life, his complete break with his mother and her other children.” The occasion for the break is yet another mystery. It must have had something to do with their disapproval or sense of scandal, but Hayek describes it as “almost as unintelligible to his relations as to us.” Twenty years after the break, his sister Harriet expressed genuine bafflement, reporting that “up to the time of his marriage he had been everything to us,” and “it was a frightful blow to lose him at once and for ever, without [one] word of explanation,—only in evident anger.”

The marriage was quiet, productive, and supremely happy, but both husband and wife suffered from a series of illnesses. In 1854, Mill believed himself to be gravely sick. He wrote:

The only change I find in myself from a near view of probable death is that it makes me instinctively conservative. It makes me feel, not as I am accustomed—oh, for something better!—but oh, that we could be going on as we were before. Oh, that those I love could be spared the shock of a great change!

But he recovered well, and it was Taylor who became desperately ill four years later. Mill wrote an appeal to a doctor: “I implore to you come immediately. I need hardly say that any expense whatever will not count for a feather in the balance.” He never came (perhaps because the letter arrived too late).

Shortly after her death, Mill wrote: “It is doubtful if I shall ever be fit for anything public or private, again. The spring of my life is broken. But I shall best fulfil her wishes by not giving up the attempt to do something useful.” On Liberty was published in 1859 and dedicated “to the beloved and deplored memory of her who was the inspirer, and in part the author, of all that is best in my writings.” Mill lived to 1873, and many of his greatest works appeared after Taylor’s death.

Remarkably, Hayek ends his book with very little about Taylor’s influence on Mill’s thought. But in fragments of the book, and in other essays in this volume, we can uncover Hayek’s views on the mysteries with which he began. Hayek agrees that Taylor’s “influence on his thought and outlook, whatever her capacities may have been, were quite as great as Mill asserts.” At the same time, Hayek concludes, “they acted in a way somewhat different from what is commonly believed. Far from it having been the sentimental it was the rationalist element in Mill’s thought which was strengthened by her influence.”

It is important to see that for Hayek, this is anything but praise. In Hayek’s view, there is an enduring opposition between true individualism and rationalism, with the latter associated with socialism (and also fascism and communism). By rationalism, Hayek meant to refer to the hubristic view that with the aid of reason, human beings can plan a social order, subjecting it “to the control of individual human reason,” rather than relying on free markets, spontaneous orders, and the working of the invisible hand as described by Scottish Enlightenment thinkers such as Adam Smith, a founding individualist.1 Rationalists, in Hayek’s account, think that human beings can effectively design rules and institutions, a “fatal conceit” that “always tends to develop into the opposite of individualism, namely, socialism or collectivism.”

Still, Hayek did not believe in complete laissez-faire. He favored a guaranteed minimum for the poor (“some minimum of food, shelter, and clothing, sufficient to preserve health and the capacity to work, can be assured to everybody”) and even a comprehensive system of social insurance. Nonetheless, he insisted that rationalism is both arrogant and dangerous, and he believed that Taylor moved Mill in its direction.

In my view, Hayek is obtuse in his conclusions about Taylor’s influence on Mill, and the evidence for a far better account comes from Hayek’s own story of their relationship. Mill cared deeply about social justice, and he came to embrace what he described as a form of socialism, above all because of the unfairness of “the present economic order of society.” But his complex writing on that topic should hardly be seen as an endorsement of centralized government planning. Mill was never a rationalist in Hayek’s pejorative sense.

Where Taylor most influenced Mill was on topics that were not the subject of Hayek’s main focus. Mill’s The Subjection of Women (largely ignored during his lifetime) was clearly influenced by Taylor’s views as expressed in her 1851 essay The Enfranchisement of Women.2 Taylor sketched many of Mill’s central arguments, and others that were more radical still, including an explanation of why married women should work outside the home:

A woman who contributes materially to the support of the family, cannot be treated in the same contemptuously tyrannical manner as one who, however she may toil as a domestic drudge, is a dependent on the man for subsistence.

On Liberty is widely taken to be an argument for limited government, and so it is. But it is crucial to see that in contending that people may be restrained only to prevent “harm to others,” Mill was speaking of the effects of social norms and conventions, not merely of government. Much of his attack was on the oppressive quality of public opinion. Taylor herself had made similar arguments more than two decades earlier, and it is hard to mistake the connections among her youthful views, his own painful experiences in the 1840s, and his passionate arguments against the tyranny of custom. His particular case for liberty emphasized the immense importance of allowing “experiments of living.” In his view, “the worth of different modes of life should be proved practically, when any one thinks fit to try them. It is desirable, in short, that in things which do not primarily concern others, individuality should assert itself.”

Here we can find the sharpest of the divergences between two of the great figures in the liberal tradition. Enthusiastic about individualism, Hayek generally prized traditions and customs. Mill did not:

Where, not the person’s own character, but the traditions or customs of other people are the rule of conduct, there is wanting one of the principal ingredients of human happiness, and quite the chief ingredient of individual and social progress.

This is a timeless claim, to be sure. But as Hayek’s book demonstrates, it is also intensely autobiographical. Mill and Taylor embarked for many years on a kind of “experiment of living” that was designed to promote their own happiness despite being roundly condemned by “the traditions or customs of other people.” But their individuality asserted itself. The worth of their different mode of life was proved practically.

All this leaves the mystery with which Hayek started: Who was Harriet Taylor? Hayek’s own verdict was clear. She “was an unusual person. But the picture Mill has given us of her is throughout determined by his own character and tells us probably more of him than of her.” To Hayek, Mill was in the grip of a delusion. Thus Hayek’s conclusion:

Behind the hard shell of complete self-control and strictly rational behavior there was [in Mill] a core of a very soft and almost feminine sensitivity, a craving for a strong person on which he could lean, and on whom he could concentrate all his affection and admiration.

Though fascinated by the scandal and the romance, Hayek rendered a cold verdict on Taylor herself. Perhaps he was right. But I prefer Mill’s own: “She was the sole earthly delight of those who had the happiness to belong to her…. Were there but a few hearts and intellects like hers this earth would already become the hoped-for heaven.”