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

When the news of the royal birth was announced yesterday part of the excitement focused on the couple’s decision to break with tradition and do things their own way. And why not?

Well, this welcome royal baby arrived in a very royal week.

After a three-day coronation ceremony, I imagine the new King of Thailand is taking it a bit easier today. And I imagine I am not alone in the world outside Thailand to have observed some of the rituals on television without really understanding what was going on and why. As an outsider it was fascinating to watch, but hard to follow.

What I found most curious was the powerful appeal to tradition – tradition that goes back a very long way and roots the present vocation in a collective national, ethnic and religious memory.

One of the misconceptions about the word ‘tradition’ is that those who value it simply want to live in the past – held captive by some nostalgic notion of a golden age of simplicity and clarity that promises security.

But, tradition has to do with the collective experience and wisdom of the past which then informs and shapes the future, giving roots to the values that underlie our common life – better seen as a fanning of the flame in the present rather than a holding on to the ashes of the past.

Tradition goes deep. Having regard to the experiences and wisdom of past generations – their successes and failures, strategies and accidents – instils the caution needed if history is not to repeat itself and change is to be properly, intelligently and soberly appraised.

For example, the central section of Isaiah in the Hebrew Scriptures is addressed to a people in exile in Babylon, proclaiming the promise that freedom is coming, that exile is ending, that they will soon go home – which sounds great.

Yet, when we dig down into the reality of the exiles’ experience, the promise also becomes something of a threat. For example, what will this mean for those who were born in Babylon and for whom the place of exile is and always has been ‘home’? How will the returning exiles – immigrants – be received back in their ethnic homeland by those who never left and regard the land as theirs? How will they negotiate a common society when, having been exiled, their notions of ‘home’ might have become stuck in a nostalgic past?

In other words, the tradition might root the people in a memory, but they still have to shape today and tomorrow by facing questions none of them has had to face before.

None of this is alien to the politics of our time. Slogans that implicitly promise that we can return to a golden age of the past are, literally, fantastic. We can shape the present and future in the light of the past, but this always demands courage, corrective and competence.