Yes I guess he is fortunate with his health and well being, but it always difficult to know how much of a person's current state of health is simply a random occurrence and how much results from that person's lifestyle and the multiple factors that contribute to our risk of illness, which of course includes our family history. Jack was liberal with his friendship towards us-in fact it proved a challenge to get away...
One factor that is known to contribute to well being is 'connectedness'. That surrounding of oneself with and the giving of oneself to, other people, some of whom we would call 'friends' of various degrees of closeness. One of the factors contributing to my own dear mother's well-being (she is 84 years old today) has been her warmth and hospitality to so many people over the years. Loneliness and isolation can literally kill us but friendship, both freely offered and freely received immunises us to some degree against a variety of ills.
Being a Christian believer provides wonderful friendships and being part of a healthy church family really adds to that. Of course I realise that not all church families are as healthy and health giving as they might be, and not everyone who has lots of friends will be fit enough to paraglide at 82 years, but maybe it makes the probability more likely.
Any way Jack has inspired me to plan for my sixties!
By the way take a listen to a great sermon here on 'spiritual friendship' by Tim Keller