A trove of letters sent by Pope John Paul II to philosopher Anna-Teresa Tymieniecka that has come to light through a BBC documentary has sparked a bushfire of speculation about the nature of their 30-year friendship.

The programme’s presenter, Edward Stourton, is convinced that there’s a romantic love story behind it – at least from her side. However in 1996 Tymienecka told biographers Carl Bernstein and Marco Politi flatly that she “never fell in love with the cardinal”, as Karol Wojtyla already was when the correspondence began in the 1970s. They were both over 50 by then and Tymieniecka was long since married and mother of three children. “How could I fall in love with a middle-aged clergyman?” she said.

The fact is that the whole world (minus a few thin-lipped progressives) fell in love with Pope John Paul II, as we saw so plainly at the end of his life, when tens of thousands kept vigil in St Peters Square as he was dying, and millions streamed past his coffin in the days that followed. In his health and strength he was a colossus, whose spiritual magnetism and huge intelligence made him impossible to ignore.

But he would not have become a saint if he had not also been thoroughly human, a man with a big heart, capable of loving both individually and universally. Love is the sine qua non for sanctity, and the celibate love of John Paul had a special intensity because it had first been given totally to God, purified and expanded there.

Of course he had close friends, some closer than others, women as well as men. Before we ever heard of Professor Tymieniecka there was Dr Wanda Poltawska, a friend from his youth and a survivor of medical experiments at Ravensbrück concentration camp who collaborated with him in defending the dignity of sex and marriage. Her publication of some of their 50-year correspondence after his death also caused a stir. The warm affection and concern they express is very similar to that of the fragments of the other letters just published.

If he loved these women in a special way it was because of common experience (war and assaults on their humanity) their intellectual and personal gifts (he shared with Tymieniecka expertise in phenomenology, a philosophical movement founded by Husserl) and his admiration for what he called “the feminine genius”.

When the book about John Paul II and women is written it would include also the Italian left-wing feminist Maria Antonietta Macciochi, who was among female cultural figures he consulted prior to issuing in 1988 his important Apostolic Letter On the Dignity and Vocation of Women. Maccioci was to defend that “meditation” -- based as it was on scriptural texts pointing to the complementarity of man and woman – as a document betraying “an unusual love of women”.

Women helped John Paul develop and express his profound “theology of the body”, his answer to the trivialisation of sex and its impact on marriage and the family in society and in the Church itself. Its fearless sexual realism is still repudiated (or simply not understood) by some older Catholics but has caught the imagination of the young.

But if anything is clear from the fragments of his letters to individual women that we have see it is that he wanted to give back to those women. Love is a very battered word today, but for John Paul it meant self-giving – in marriage and friendship, mutual self-giving. This is one of the great themes of his writing on the subject. In admiration and gratitude he gave what he could to his close female friends and collaborators: the deep and strong affection of a pure heart. Our age, which knows so little of purity – or, truth to tell, love -- struggles to understand that.

The first place in his heart, however, went to the woman whom he represented on his coat of arms with a simple M set in one quadrant formed by the Cross. Mary, surely, was the woman in his life, the one who watched over his motherless youth and who formed his piety through the “living Rosary”. All the others took their place beside her.

Carolyn Moynihan is deputy editor of MercatorNet.