|Photograph: Garry Weaser for the Guardian|
At virtually every conference I've attended as a doctoral candidate, I've noticed a similar reaction whenever I strike up a conversation with my fellow students.
They exude a faint, but perceptible air of deference.
Sadly, this is not in recognition of my academic brilliance, but my greying hair and crow's feet, which tacitly suggest that I am more qualified and experienced than I actually am.
You may be as young as you feel, but sadly, initial impressions tend to be based on how old you look.
When I reveal that, though I am 42, I am in fact a student, the response is invariably, "Oh, I thought you were an academic." I can't help feeling that this reaction masks an unspoken enquiry: "So why are you doing a PhD at your age?"
This is certainly a question I've asked myself over the past three years of my part-time doctorate, and there still doesn't seem to be any rational answer.
I'm spending money I can ill-afford in the pursuit of a qualification, which may or may not offer the slenderest of chances of becoming an academic. I was warned, of course, that the arduous journey of a humanities PhD doesn't offer the guarantee of a job at the end of the process.
Entering an already saturated job market
A former supervisor whom I contacted for a reference prior to resuming study after a 20-year hiatus told me that I was more or less wasting my time in seeking to enter a saturated job market populated by those younger, fresher, hungrier and less shop-worn than I.
A newly qualified doctorate-holder in their 20s has, it's safe to say, enjoyed a fairly seamless career progression: BA, MA, PhD. They are straight arrows - I am an unguided missile by comparison, with a career history built upon under-performance in a range of fields.
A nagging voice that whispered "this isn't what you should be doing with your life" sabotaged any commitment to establishing a presence in the corporate world.
Of course, there are benefits to beginning a PhD in later life. Being older doesn't necessarily make you wiser, but in my case, it has made me more disciplined about the process of writing.
After graduating from university in 1994, I meandered from job to job and eventually trained as a journalist. I hated the job, but it taught me to write to strict deadlines, an attribute which has proved invaluable when juggling the demands of a full-time job and two young children.
I don't have the option of planning a day of study - I fit my studies in around my life. I typically squeeze in my doctoral work during evenings and weekends, but in fact, trying to segregate family, work and PhD time is virtually impossible - my doctoral work is always on, running as a background programme throughout the day.
I have not experienced an unbroken night's sleep for the past five years - I am invariably up in the small hours banishing ghosts, dispensing milk or searching for misplaced comforters. As I have discovered, chronic sleep deprivation makes sustained concentration a daunting task.
If you begin a PhD in your early 20s, there's a strong presumption that this represents a career choice. If you begin a doctorate in later life, this is often interpreted as a desire for intellectual stimulation, rather than an ambition to secure employment as a teacher and researcher.
Older doctoral candidates seem under-represented in the teaching and lecturing undertaken by postgraduate students.
Thanks to the demands of work and family life, I don't enjoy many networking or social encounters with my peers - but I do enjoy the benefits of a stable home environment and a steady source of income. Instead, I've been able to build up a roster of contacts on Twitter and other social networking sites.
Why I want to work in academia
Why do I keep going? Because after living in the banality of the corporate world, I have a renewed respect for academia, for open-mindedness and intellectual honesty.
It's true that higher education is becoming increasingly corporate - academics are hostage to the jargon of marketers, and are being forced to demonstrate that their research has an impact beyond the scholarly community, and that their teaching embodies "employability", irrespective of its intellectual merits.
I recognise that there is a correspondent ruthlessness within academia - the demands of maintaining an impressive roster of publications, of success in securing funding, and of competing with other highly intelligent, motivated people for a dwindling pool of jobs.
But there's also the very real joy of research, of reaching the limits of your intellectual boundaries, of being invited to contend with ideas that matter. And that's why I continue along the lonely road of the PhD - I've revived a part of me that I'd lamented, thinking it gone forever. And seeing it revived - and occasionally flourishing despite all life's obstacles - is enough.
This week's anonymous academic is studying for a humanities PhD at a Russell Group university.
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