The commemorations of Marx's 200^th birthday have done at least one thing: they've reminded me of Britain's abject intellectual decline.

Listen, for example, to this debate about Marx (34 min in); Paul Mason's interlocutor couldn't tell the difference between Marx and a bucket of fish.

Contrast this with a few decades ago. Then, if you wanted a critical assessment of Marx, you might reasonably have asked Leszek Kolakowski, Samuel Hollander or Isaiah Berlin - men who, agree with them or not, knew what they were talking about. Today, his most high-profile critics are ignorant gobshites.

This, however, is but one example of the intellectual decline of public life. For me, the BBC's recent series, Civilisations, contrasted horribly with Clark's version. Most programmes seemed to be random observations with no narrative flow - and directors who lacked the courage to have the camera linger on the art as Clark's did.

In the same vein, compare Jacob Bronowski's The Ascent of Man to, say, Brian Cox.

More strikingly, can you image the BBC devoting 50 minutes to two old white men discussing Wittgenstein, as it did in 1976?

This is mirrored in our politics. On both front benches today there are pitifully few people one could call intellectuals (as distinct from intelligent): Jesse Norman and Barry Gardiner are the only ones I can think of immediately. The 60s and 70s, however, gave us Crosland, Foot, Jenkins and Crossman among others. And although Thatcher was considered no great intellectual in her time, she peppered her speeches with references to Hayek, Friedman or Popper. Can you imagine Theresa May citing similar men? Are there even any?

I know, I know, I know. You might think this is a very selective reading of history: there have always been lots of buffoons in politics (some Scottish miners on the Labour side and landed oafs on the Tory) and lots of crap on TV. Nor of course is the BBC an intellectual desert: any organization employing Jim al-Khalili and Helen Castor is doing something right. But I suspect there is at least a grain of truth here, even before mentioning the obvious dumbing down of the Today programme. (I'll leave others to say whether this applies to other fields such as literature, music and other arts.)

This poses the question. Assuming I'm roughly right, why might this be?

It could be a legacy issue. Back in the 80s, academia was demoralized and in decline. Several good judges told me that if I got a PhD I would be unemployable in the UK. I wouldn't have been a great academic, but I'm confident that many people who might have been got the same advice and went into finance, the law or other jobs.

And those who did become academics have faced another problem. The effect of the Research Assessment Exercises (and I suspect the intention) was to force academics to publish unreadable and unreplicated papers rather than to think or to engage with the public. (I gather that their successor, the REF, is a little different but its long-term effect is yet to be evident).

The upshot of these developments has been a loss of public intellectuals. Just look at the people who appeared on Bryan Magee's Men of Ideas: are there even equivalents today?

Perhaps, though, there's something else - the rise of consumer culture. There was a time when politicians and the BBC considered what was best for the country - which of course wasn't wholly incompatible with their self-interest. "The man in Whitehall [and Broadcasting House] knows best." Long debates about philosophy might not have been what the public wanted, but BBC bosses thought they were good for us. Equally, whilst Thatcher and Attlee disagreed about almost everything they had at least one thing in common - a loathing of referenda. They thought political decisions should be taken by the people paid to do so. And because such decisions were tricky, they required people of intellect.

Today, though, that ethos has been replaced by the idea that the customer is king and that giving punters what they want is all that matters. If political and TV programming decisions are determined by opinion polls and focus groups - and failing that by some image of a narrow-minded voting and viewing public with no attention spans- there'll be no room for the high-minded. Debate will be replaced by an exchange of sound-bites.

Now, this shift isn't wholly wrong: there are times when we should indeed trust the public. But I wonder: in abandoning the "Man in Whitehall knows best" attitude, might we have lost something, especially when it has coincided with other social trends.