elcome. And congratulations. I am delig you could make it. Getting easy, I kno, I suspect it tle toughan you realize.

    to begin o be rillions of drifting atoms o assemblein an intricate and intriguingly obliging manner to create you. Its an arrangement sospecialized and particular t it ried before and  t many years (icles , cooperative efforts necessary to keep you intact and let you experience t generally underappreciated state knoence.

    oms take trouble is a bit of a puzzle. Being you is not a gratifying experience attomic level. For all ted attention, your atoms dont actually care about you-indeed, dont even kno you are t even kno ticles, after all, and not even t is a sliging notiont if you o pick yourself apart om at a time, you omic dust, none of o a single overarco keep you you.

    t atoms are fickle and time of devotion is fleeting-fleeting indeed.

    Even a long o only about 650,000  modestmilestone flas, or at some ot ts, for reasons unknoomsly disassemble, and go off to be ots it for you.

    Still, you may rejoice t it  all. Generally speaking in t doesnt, sofar as ell. toms t so liberally and congeniallyflock togeto form living tly toms t decline to do itelse may be, at try life is curiously mundane:

    carbon, rogen, a little calcium, a das dusting ofots-not find in any ordinary drugstore-and tsall you need. t toms t make you is t they make you.

    t is of course the miracle of life.

    atoms make life in oty else;indeed, t ter or air or rocks, nostars and planets, no distant gassy clouds or smake terial. Atoms are so numerous and necessary t  t actually exist at all. t requires to fillitself icles of matter or to produce ligy and ties on ually be a universe at all. For t time t. toms and no universe for to float about in.

    t all anywhere.

    So toms. But t t you oms and t t of  you o be y-first century and smart enougo kno, you also o be traordinary string of biological good fortune. Survival on Eartrickybusiness. Of t ed since time, most-99.99 percent-are no longer around. Life on Eart onlybrief but dismayingly tenuous. It is a curious feature of our existence t  t is very good at promoting life but even better at extinguis.

    ts for only about four million years, so if you  be as fickle as toms t made you. You must beprepared to c yourself-sion,everyto do so repeatedly. ts muco get from quot;protoplasmal primordial atomic globulequot; (as t andSullivan song put it) to sentient uprigo mutate neraitsover and over in a precisely timely manner for an exceedingly long  3.8 billion years you ed on it, groy sails, laid eggs, flicked tongue, been sleek,been furry, lived underground, lived in trees, been as big as a deer and as small as a mouse,and a million tiniest deviation from any of tionary ss, and youmigony sop of your y feet for amouthful of delicious sandworms.

    Not only o be attacime immemorial to a favoredevolutionary line, but you remely-make t miraculously-fortunate in yourpersonal ancestry. Consider t t for 3.8 billion years, a period of time older tains and rivers and oceans, every one of your forebears on bottractive enougo find a mate, o reproduce, and sufficiently blessed by fateand circumstances to live long enougo do so. Not one of your pertinent ancestors randed, stuck fast, untimely ed from its lifes quest of delivering a tiny cic material to tpartner at t moment in order to perpetuate tarycombinations t could result-eventually, astoundingly, and all too briefly-in you.

    t  icular  from tall to ttle of t someturned into us, and alsosome of s a great deal to cover, of course,  isnt really. Itcouldnt be. But ime  is.

    My oarting point, for s rated science book t I ext ered, unloved, grimly y-but near t it ration t justcaptivated me: a cuta  intot ing about a quarter ofits bulk.

    Its o believe t time ionbefore, but evidently I  for I clearly remember being transfixed. I suspect, in y,my initial interest e image of streams of unsuspecting eastboundmotorists in tates plunging over tral America and t gradually my attention did turnin a more sco tific import of tion t ted of discrete layers, ending in ter  as to tion, and I remembert;?quot;I didnt doubt tness of tion for an instant-I still tend to trust ts of scientists in trust tion-but I couldnt for t  no eye rate, could look like and be made of. to me t  amiracle. t ion h science ever since.

    Excited, I took t nig before dinner-an action t I expectprompted my moto feel my fore-and, starting page, I read.

    And   exciting at all. It  actually altogether comprehensible.

    Above all, it didnt ansions t tration stirred up in a normalinquiring mind: ? And if it isburning a t  to touct of terior melting-or is it? And  burns itself out, o t sink out?

    But trangely silent on sucails-indeed, silent on everytanticlines, synclines, axial faults, and t o keep tuffsecret by making all of it soberly unfato suspect tt altogete impulse. to be a mystifying universalconspiracy among textbook auto make certain terial t rayedtoo near teresting and  least a longdistance peresting.

    I no ters imotey, and tim Flannery are t jump out froma single station of t (and ts not even to mention te but godlike Ric sadly none of te any textbook I ever used. All mine ten bymen (it ing notion t everyt te ers end ion of questions time. So I gre science  suspecting t it needntbe, and not really t it at all if I could . too, became my position for along time.

    ter-about four or five years ago-I  t moonlit ocean, o me ainuncomfortable forcefulness t I didnt kno t t I o live on. I y but t Lakes. Didnt est idea. I didnt knoyime or less, and  or not. (I am very pleased to tell you t until te 1970s scientists didnt knoo tions eit didnt talk about it very audibly.)And ocean salinity of course represented only t sliver of my ignorance. I didntknoon ein, didnt kno understands could look at a layer of rock on a canyon ell you   kno, uned urge to knotleabout tters and to understand . t to me remained test of all amazements-ists . s rocks are or er? arted and  om? And o t-or perists so often seem to kno till cant predict aneartell us o tednesday?

    So I decided t I e a portion of my life-t nourns out-toreading books and journals and finding saintly, patient experts prepared to ans ofoutstandingly dumb questions. to see if it isnt possible to understand andappreciate-marvel at, enjoy even-ts of science at a level tisnt too tec isnt entirely superficial either.

    t  folloended to be.

    Anyo cover and muco do it, so lets begin.