Maybe you’re fascinated by Ada Lovelace already. If not, I hope by the end of Ada’s Algorithm you will be.

I became intrigued by Ada myself – and soon enthralled by her – while writing my book Jacquard’s Web: How a Hand-Loom Led to the Birth of the Information Age (2004), by which time a general interest in Ada’s work was well established. There is a popular software language called Ada, which was originally developed by the U.S. Department of Defense in the late 1970s to unite a host of different programming languages. In 2009, an international Ada Lovelace Day was launched on London’s Southbank to celebrate the achievement of women in science, technology, engineering and mathematics. There is a Hollywood movie about Ada (written by Shanee Edwards), Enchantress of Numbers, in development.

It would, at least at first glance, appear that science has a chequered record of treating women as equals of men. Indeed, female staff at Bletchley Park, the wartime decryption headquarters that cracked German ciphers, were largely unrecognised for their painstaking work. Meanwhile Rosalind Franklin, who did much of the Nobel Prize–winning work on DNA, was ignored in all official recognition of the deduction of the existence of the double helix, to the embarrassment of the male scientists involved.

Whether this is historically a case of sexism or social conditioning of both genders is beyond the scope of this book. (Change is afoot for the future – as Elinor Ostrom quipped on becoming in 2009 the first female Nobel Prize winner for economics, ‘I won’t be the last.’) What is clear, though, is that there is a surging interest in the history of women who have contributed to and been involved with science.

While Lord Byron, Ada’s father, cast a long shadow over her life, she was just over a month old when they parted company forever and so she never met him in any meaningful sense. A much more durable person in her life was Lady Byron, who had been well educated by her enlightened parents and brought up to move in liberal circles. Lady Byron maintained a ferocious control over her daughter’s life and, as it would turn out, death.

Ada Lovelace’s story is most closely interwoven with that of her close friend Charles Babbage, the scientist who invented the first mechanical computer. Like Babbage, Ada was tireless in the pursuit of knowledge. On Monday, August 14, Ada wrote to him:

I wish to add my mite towards expounding & interpreting the Almighty, & his laws & works, for the most effective use of mankind; and certainly, I should feel it no small glory if I were enabled to be one of his most noted prophets (using this word in my own peculiar sense) in this world.

Ada and Babbage’s letters became so intimate that they clearly suggest that they had what was essentially a romantic friendship.

Unlike Babbage himself, Ada Lovelace saw beyond the immediate purpose of his inventions. He had little interest in such speculations and appears to have seen his inventions as mere calculators. But Ada believed that a whole new area of discovery awaited once real-world and abstract mathematics could be linked through calculations that were beyond the scope of human abilities. She had a vivid, thrilling and disturbingly prescient vision that such a computer, for example, might handle “pieces of music of any degree of complexity or extent”: a familiar and even everyday truth over a century and a half later but inconceivable to scientists at the time.

Ada was passionate, kind, imaginative, excitable and emphatic. She loved emphasising words in the letters and documents she wrote by underlining them (such words are italicised in this book where she is quoted). She was regularly in poor health and used mathematics as a way to regain her focus. Later in life, when she was in severe pain from cancer, she would use medication we now recognise as mind-altering drugs. After a long and excruciating battle with the disease that she appears to have suffered without complaint, she died of cancer at thirty-six, the same age at which her father Lord Byron passed away.

One of the fiercest criticisms of Ada is found in The Little Engines That Could’ve (1990), a thesis by Bruce Collier. This thesis, an otherwise shrewd and useful account of Babbage’s work, contains much highly informed technical material. But Collier wrote this about Ada:

There is one subject ancillary to Babbage on which far too much has been written, and that is the contributions of Ada Lovelace . . . It is no exaggeration to say that she was a manic-depressive with the most amazing delusions about her own talents, and a rather shallow understanding of both Charles Babbage and the Analytical Engine . . . To me, this familiar material seems to make obvious once again that Ada was as mad as a hatter . . . I will retain an open mind on whether Ada was crazy because of her substance abuse . . . I guess someone has to be the most overrated figure in the history of computing.

I was keen to contact Collier to enquire whether he would, more than twenty years later, still subscribe to this opinion about Ada but unfortunately he passed away some years ago.

In comparison to this modern opinion from someone who never knew Ada, let’s see what Charles Babbage himself thought of her. On September 9, 1843, he wrote these words to Michael Faraday, the nineteenth-century polymath who discovered electrolysis and magnetic induction:

[T]hat Enchantress who has thrown her magical spell around the most abstract of Sciences and has grasped it with a force which few masculine intellects (in our own country at least) could have exerted over it.

As for claims that Ada was mentally unstable, there simply is no reliable evidence for this and I believe such claims are made, at heart, because some computer historians in the past have not liked the idea that a woman could have to some extent stolen Babbage’s thunder, though from posterity’s perspective this is exactly what Ada to some extent did. I do think that towards the end of her life, when she was dying in great pain and only had laudanum (a tincture of opium) as an inadequate palliative to ease her desperate situation, Ada was often not herself, but anyone, of either sex, so afflicted would be unlikely to be themselves.

Moreover, on the website of “The Ada Initiative,” which states its aim as supporting women ‘in open technology and culture,’ there are some extremely wise and justifiable words on the matter that Ada was mentally unstable or even insane and could not therefore have done any useful intellectual work to help Babbage. As “The Ada Initiative” points out:

Interestingly, these arguments are rarely used to question men’s authorship of joint works; indeed, mental instability or difficult personalities sometimes seems to add to the reputation of male scientists and mathematicians: Nikola Tesla, John Nash and Isaac Newton to name just a few.

I think this point is very well made. I do indeed believe that accusations of Ada being mentally unstable are unsustainable based upon the documentary evidence available today (which, to be fair to the late Bruce Collier, he may not have fully known about) and that such criticisms are often uttered by men for sexist reasons rather than for having any rational basis. But should we be surprised that men, who have after all often for centuries been putting women down and relegating women to a secondary role in politics, culture and all branches of the arts and sciences, often feel profoundly uncomfortable about allowing Ada a highly significant place in the pantheon of the greats of the history of computing?

I hope that this book will make clear that Ada Byron, later Countess of Lovelace, Lord Byron’s only legitimate daughter, should without doubt be included in that pantheon and on the list of overlooked women who were not encouraged to fulfill their potential merely because of their gender. There has certainly so far been no biography of Ada that fully defends the genius of her thinking, that genius that prompted me to write this book. Ada’s grasp of complex questions came with such ease that she was able to see beyond it to regions of speculation and prescience where others needed to work hard to even understand the questions themselves.