This is the script of this morning's Thought for the Day on BBC Radio 4's Today programme:

I have just got back from the reading of fat books on holiday. The one that grabbed me this time was Tom Holland's 'Dynasty: The Rise and Fall of the House of Caesar'. It all sounded so contemporary. The voice in my head kept repeating the plaintive phrase from the book of Ecclesiastes, “There is nothing new under the sun”. Power, violence, subterfuge, ego, leadership struggles, populism and politics – it's all there. It always is.

I also kept hearing the line from Proverbs: “Where there is no vision the people perish.” The problem with vision is that it emerges from memory. Rabbi Jonathan Sacks said this week that Judaism is a religion of memory. So, I would argue, is Christianity. Both remind us, for example, that empires come and go, that hubris is ultimately embarrassing, and that history sadly repeats itself. Christianity makes no sense at all without rituals that are there to compel compulsive amnesiacs to re-member their story: in this case that by recalling that we were once slaves, we will refrain from treating other people like slaves; that we are set free to serve; that we are to do justly, love mercy and walk humbly with God (and one another). For Jews the Passover goes to the heart of this memory; for Christians the Eucharist re-tells the story into which we fit ourselves and shape our future.

We can only know who we are if we know from where and from whom we have come. The problems emerge when either we think we have been born into the ultimate 'now' – that nothing valuable went before us – or we choose the bits of memory that are convenient to our present or future self-justifications.

And that is as dangerous for nations, continents and communities as it is for individuals or religions.

With this in mind, and having read about the Caesars, I wonder if every government should appoint a Cabinet Historian to remind it of the past and challenge policy for the longer-term future in the light of experience.

Of course, all readings of history are partial, and memories are always susceptible to selectivity. But, some of the challenges we face (for example, in the light of Brexit) would be informed by a sober re-membering. Memories are short, but how will anyone born in this millennium understand Russia and Ukraine when they have no experience of the Cold War – and a world divided not just by affluence but by starkly competing ideologies? Memory is not quite the same as history, but both can become commodities in struggles for power, as the biblical narrative reminds us.

Well, I won't hold my breath, but without a memory the people cannot form a vision. And without a vision the people perish.