This is well-trodden territory for amateur philosophers like me. I am used to having my purpose questioned by staff, as in, "What the hell does the principal do all day?" And to musing on the meaning of life in a "Why are we here, what is our purpose on earth?" sort of way. So answering Mr Foster's question should be a piece of cake.
But I have to avoid some common philosophical traps, such as arguing from "inference". Take Bertrand Russell's chickens. Every day, the farmer's wife comes out of the door at precisely 8am and throws them their feed.
Naturally, the chickens form an opinion of both the wife and the world in general: namely that the wife is fundamentally good and the world benevolent and predictable. But one day at 8am she wrings their necks.
Inference undid the misguided hens.
It can do the same to us. Because FE colleges exist, we would be wrong to infer that they need to. Because people flock to them as beacons of benefit and they deliver social mobility to millions, we are wrong to infer that this state of affairs will or should continue for even another minute.
Think of the DfES as the farmer's wife.
Hume, the philosopher, taught me never to trust miracles as a basis for belief. If the sun stops in the sky and is witnessed by a group of religiously-educated schoolgirls, you have a choice of two things to believe: either the laws of the cosmos really were suspended for a few moments, so the earth stopped in its orbit without triggering a train of cataclysmic natural disasters, or a group of hysterical girls lied and couldn't get out of it without being walloped by their mothers.
Hume advises us to believe the lesser miracle. So, do FE colleges miraculously break all market laws by doing the stuff nobody else wants to do for people who aren't sure they want to do it, widening participation without cataclysmic social upheaval? Or, are all college principals inveterate whingeing liars, out to preserve their well-paid careers? Believe the lesser miracle, folks. The Government will.
John Stuart Mill advocated action which did the "greatest good for the greatest number". Somewhere there ought to be a John Stuart Mill college - because he really did seem to encapsulate what FE is about.
On the other hand, he might have changed his mind if he had been stranded on a desert island with eight hungry cannibals. Offering himself as dish of the day is then bang in line with his own philosophy. So, context determines the moral value of an action.
If there is universal affluence, with skills needs met, everyone employed to their full potential and no school drop-outs, then FE is a drain on the public purse and the greatest good would be to abolish it and spend the money on something valuable.
If, however, the context is somewhat different and there is still underprivilege in need of assistance, ignorance in need of enlightenment and talent in need of recognition, then the greatest good might well lie in institutions which set out to assist, enlighten and recognise citizens in need.
But the real philosophical eye-popper, of course, is perception. How can we know anything for certain when all knowledge has to be filtered through unreliable senses.
These are the great epistemological issues. If a success rate falls in Epping Forest, does it make a difference if inspectors are not there to measure it? We poor mortals should not be deceived by the evidence of our senses. We perceive daily miracles in our classrooms, but need them confirmed by inspectors. We are conscious of doing great good, but need league tables to prove it is real. And who is this "we" in any case? What is the FE sector, let alone what is it for?
Deep stuff. I'm being told I work in a college of uncertain purpose, whose value and achievements can be fundamentally questioned, despite years of detailed inspection reports, performance review, success-rate improvements, strategic plans and funding bodies.
Clearly, I have fallen into the greatest philosophical trap of all. I thought FE was real. If it isn't, then nor am I. My children have often said so ("Dad, you are so unreal!") And that's the trouble with philosophical questions about reality and purpose. You end up disappearing up your own cogito ergo sum. But there is a real perception problem; it belongs to new Labour and explains the quest for purpose. A colleague of mine recently chided a very senior government minister for not supporting FE more - after all, he said, we are working-class institutions. "There is no such thing as the working class," came the reply. So if Labour thinks it has abolished the underdogs, what's the point of their kennels?
Graham Jones is principal of Sutton Coldfield college