I teach part of the year at an American elite scientific institution, Caltech, where my classes are very un-elite Englit. I mentioned in passing to a "Techer", as they call themselves, that in my country universities were closing down departments of chemistry.

I expected the response one would have got from a prelate on being told that Henry VIII had just resolved to dismantle the monasteries.

What in fact Young Big-Brain did was shrug his shoulders and say, "Yeah, it's an old subject." What's the problem, prof? He himself was majoring in an exotic new combo - biophysics, astrogeology or something.

For me "old" meant venerable: Chinese sages, vintage wine, the changing of the guard at Buckingham palace. The English department I taught in, UCL (founded in 1828), prides itself on being the oldest in the country. For YBB, "old" meant the equivalent of Rod Stewart (or me).

Science at Caltech disdains "departments" and organises its research and teaching activity within large fluid "divisions". New combinations are constantly taking place. Whole divisions have disappeared: x-ray research, for example. "Disciplines" - core organisational principles - seem healthily uneroded by these ever-dividing, kaleidoscopic formations.

All of which raises two questions: (1) how "adaptational" should subjects be to forces within and outside the academy? How should they bend with, or resist, the tides of fashionability? And (2) can they, perhaps, control those tides - or is that Canute thinking?

All this is a wind-up to my specific subject here. Is English as an academic pursuit dead, dying, moribund, or on the verge of a great new chapter in its long history?

English - within living memory - was once the queen of the curriculum: the chemistry of the humanities. Ruefully looking back half a century to the 1950s, Frank Kermode, the greatest of our literary critics, recalls: "There was in those days a general belief, now weirdly archaic, that literary criticism was extremely important, possibly the most important humanistic discipline, not only in the universities but also in the civilized world generally."

In those days the subject mattered. Why does English matter less in 2006? Or hardly matter at all? It is not numbers. In a week's time, when the annual A-level results come in, English will again be, by enrolment, the most popularly chosen option and the grades historically sky-high.

In terms of feet, the youth of Britain vote every year. They love English. But, one has a sneaking feeling that, like water, they follow the line of least intellectual resistance. It is easier, and more fun, to "discuss" Birdsong or Talking Heads than - say - to master differential calculus or those other hard topics that the young British foot is determinedly marching away from, year on year.

English recruits massively. But is it still a discipline? Does it even believe in itself? In the era Frank Kermode is nostalgic for, English was sustained in its self-importance by John Newmanesque (The Idea of a University) idealism. The academy enshrined society's highest values. Those values were expressed, in their noblest form, by literature. To engage with the complexities of literary expression (no easy task) was to have that nobility rub off on you. It was a benign spiral that kept English, like a ping-pong ball on a fountain, bobbing away at the top of things for decades.

Since the 1950s, much has happened to the subject. Two strong forces have reshaped English - both, as it happens, emanating from outside England. One was "relevance", mobilised at Modern Language Association conventions in the US in the 1960s. Literary study, it was felt, should be utilised as an instrument of social progress in the essentially non-academic cause of civil rights, equality, decolonisation, and class struggle.

Out with Heart of Darkness (dead white man racism) in with Rigoberta Menchu Tum. No more ping-pong ball.

The other force that has redefined English is, notoriously, "theory". This injection of advanced thought has undeniably stiffened the subject intellectually, but exclusively at the research/scholar end rather than the A-level end of operations. English today is like a badly blended fondue, with a mass of easy stuff at the bottom and a thin layer of brain-wrenchingly difficult stuff at the top.

Thus, when you interview candidates for admission, they will blandly inform you that they "really like" Sylvia Plath as if that was all that needed to be said, critically. Meanwhile, 200 metres away, in the library, lie shelves of unconsulted journals whose contents are comprehensible only to hierophants. Where, if anywhere, is the connection?

It is instructive to dip into the current issue of Nineteenth-Century Literature lying, resolutely unborrowed, on those shelves. NCL is generally top-rated. To have an article accepted looks terrific on the CV. The journal was founded at UCLA in the early 1950s (those golden years) as The Trollopian. In those early days it carried enthusiastic pieces about the Chronicler of Barsetshire (eg did Anthony really write his novels before breakfast? What, now we think of it, did he eat for breakfast?)

The journal was, after a few numbers, renamed Nineteenth-Century Fiction. For the next half-century, NCF faithfully reflected the shifting intellectual fashions of the academy. Just recently it has renamed itself, again, Nineteenth-Century Literature, to include poetry and cultural history.

The latest issue of NCL is a "special", devoted to Lesbian Aesthetics: Aestheticising Lesbianism. One can feel a strong vibration of "relevance" - at a period when gay marriage is tearing the US apart and losing election after election for the Democratic party. The general tone of the issue is leftist-feminist.

One can also feel the bracing presence of high theory. This issue of NCL carries, for example, the discovery, by ingenious forensic analysis, of "female marriage" as a central feature of Trollope's Palliser novels. The old fellow will doubtless be spinning like a top in his grave at Kensal Green.

The journal also has an article entitled Sarah Jewett and Lesbian Symmetry. The author, Melissa Solomon, helpfully explains what her title means: "My working definition of lesbian symmetry is the symmetrical correspondence of size, shape, beauty, proportion, form or feeling allegedly visible or operative between, and in turn supposedly the result of, the corresponding bodies of lesbians - lesbians ever and always illustrating symmetry of form, of one kind or another."

Now we know.

Browsing this issue of NCL (a journal on whose editorial board I sit, incidentally, despite the theoretical thorns in the cushion) inspires the thought, can you teach an old (really old) academic subject new tricks? If you put Trollope through this ideological mangle, does he come out Trollope the other side? Likewise Sarah Jewett. If you do a lesbian symmetry job on her, is she still the author of the universally loved short story The White Heron?

Is English, as a subject, remaking itself by pondering the aestheticisations of lesbianism, or the lesbianisation of aesthetics? Is this the elixir of academic life, or merely a change of embalming fluids? Worst scenario: is English headed, like x-ray research, into the dustbin of academic history, muttering incomprehensibly to itself as it goes?

The dust on the learned journals in the library (not to say their gristly contents) predict extinction and irrelevance. But there is hope, surely, in the sound of all those young feet tramping towards the subject - even if they studiously (or unstudiously) don't stop off at the learned journal shelf while making for the books they manifestly "really like."