My body is made of trillions of cells grouped together. Most of them contain DNA, so they are indeed “me” at a very deep level. Individually, these parts of me are born, live and die each day. In fact the cells that make up my outside – the epithelial cells of my skin – are some of the youngest cells I have. People spend millions of dollars on anti-aging creams for their skin when the cells themselves are only a few weeks old.
The cells in my stomach lining live only a few days (probably less when I eat something spicy). The red blood cells that flow through my veins rarely last more than six months. While the cells in my major organs may be months or years old, most of them have been replaced at some time in my life, perhaps twice, perhaps more.
Some cells – such as the ones making up the lenses of my eyes, the muscle of my heart and the neuron cells that send brain impulses throughout my body – don’t get replaced. However, they were part of me before I was “me”, dividing and dividing while I was in the womb, pre-dating my official date by up to nine months.
My body is made of something like 7,000,000,000,000,000,000,000,000,000 atoms. About fourteen nitrogen-14 atoms are created in my body every minute from the decayed remains of the carbon-14 radioisotope. The carbon-14 itself is not that old as far as atoms go. Sadly, a number of them were probably created in the last sixty years or so during the age of above ground nuclear tests along with some atoms of caesium-137 and strontium-90 that lurk deep within the marrow of my bones.
As Carl Sagan liked to say, “We are made of star stuff”. Atoms of carbon and oxygen, potassium and iron in my body were created in the cores of ancient stars. The zinc and selenium, iodine and even the silver in my fillings required the tremendous heat and pressure of an exploding supernova to come into being.
All of these atoms are not only older than me, but all of us as a species, our planet and even our solar system. And some – perhaps most – of the hydrogen atoms that make up two-thirds of my atomic population date back to the time when the universe first cooled down enough after the Big Bang for baryonic matter to exist, somewhere around thirteen billion years ago.
I am somewhere between 1 minute and 6.8 x 1015 minutes old; you’ll forgive me if I don’t answer with greater precision. My age is irrelevant. It’s inaccurate at best and breaks down laughably as you get technical about it. It’s a measure of how long I have been an individual entity, nothing more. It has no bearing on who I am. It has no bearing on how I think, act or dress, what I buy or watch on television. As far as birthdays are concerned, they are absolutely meaningless. They are a good excuse to eat cake and should be given no more credence than that.
And the fact my 41st birthday happens to be coming up this week has nothing to do with my attitude.
“Do I contradict myself?
Very well then I contradict myself,
(I am large, I contain multitudes.)”