Human beings are wired to find intrinsic value in certain things. Art, music, puzzle solving, beauty, achievement, scientific knowledge, friendship, fine tasting food, travel experiences, charity work. Even life itself has some intrinsic value that we recognise. Ultimately none of these things has permanence and the pursuit of them all is absurd in some sense.

All of these are things that transcend our animal needs and desires. We value them not because of their ultimate usefulness or their needfulness, but because they have intrinsic value. Not ultimate value, but intrinsic value nonetheless.

Trying to fill your life with as many nice experiences as possible before you die only exaggerates the impermanence of our physical lives. And striving to "leave a legacy" for future generations can distract us from the intrinsic value of things that only we can experience and appreciate, and necessarily only in our lifetimes.

I'm absolutely desperate for the New Horizons spacecraft to finally arrive at Pluto next year. I'm going to look at every photo that thing sends back and be thrilled at having lived at precisely the right time to see it. And I'm going to keep looking and soaking it in until I am sick of that sucker. I'll read every article on it. Not because I think that it's going to have any meaning in the broader framework of my life (I'm not a planetary scientist), but because that will be an experience only people in my generation can have. To me, that rock will be beautiful, no matter how ugly and devoid of life it looks.

The same is true of a day's work. Any such day is probably meaningless. But at the end of it you can look at what you've done and derive satisfaction from it. Not permanent satisfaction, so that you don't have to do it all over again tomorrow. But real satisfaction that only you can experience.

Once I read a geology textbook, and learned about how the mountains are pushed up by continental shelves pushing together and worn down by erosion. Layers of sediment get uplifted. Earthquakes cause faults, and so on. After reading enough, I actually started to lose the sense of the beauty of mountains. All I saw was mechanical processes at work.

But this didn't last. Eventually, my innate sense of beauty captivated me again, so that when I look at mountains I am filled with wonder and a deep sense of awe. This despite the fact that I still know precisely how they got there, scientifically speaking.

I'm unsure whether the intrinsic value there is in the mountain itself or in my appreciation of it. But for that moment when I can actually visit a mountain, when I can actually have that experience, I appreciate that beauty.

But somehow, sitting around all day looking at photos of beautiful mountains, or even living right under one, isn't going to make me enjoy the rest of my life. The mountain is an experience I get to have irregularly. In this way, the intrinsic value of that experience catches me by surprise.

I even think that if I got on an aeroplane tomorrow to fly to a mountain to see it, I wouldn't be that affected by it. I'm sure we can do many things to increase our enjoyment of life, but I think that we have to be careful of believing that if we keep feeding experiences to ourselves we'll keep enjoying them. Treasured experiences can be very opportunistic. They depend on a happy coincidence of circumstances which I am uniquely able to appreciate at that time and place.