Bits make up ephemeral things, such as the packets of information that carried this column from Silicon Valley to The Independent's offices in London.
Atoms make up solid, dense things, such as rocks and government committees .
Atoms are good, from my particular viewpoint, when they are part of nifty things like godchildren or ice cream or good Pinot Noir; they're bad when they're part of things that I'm not so fond of, such as things that hurt.
A lot of attention has been paid recently to bunches of collectively hurtful atoms: the atoms in a freight train, the atoms in a pillar in a traffic tunnel in Paris, the atoms in molecules of alcohol in a French chauffeur's blood.
Bits can hurt, too.
Many observers saw a clear connection between the aggressive attention of the paparazzi and the death of Diana, Princess of Wales. Those intrusive, sometimes embarrassing images often travelled as bits over networks to newspapers and broadcasters, as did the big paychecks that had encouraged the ceaseless stalking.
Innocent individuals and businesses have been hurt by careless or malicious slander carried by newsgroup and e-mail bits.
The bits themselves are innocent, of course, just like the atoms. They're just doing their job, atoms holding up the universe and bits making parts of it go.
The guilty parties are inevitably other people: bits don't hurt people; people hurt people.
It's a privacy issue: I don't want any interlopers crashing my private space, whether atomic or bit-delimited. Neither your errant freight train nor your flaming, slanderous e-mail are welcome here at gulker.com.
But bits, by which I mean the way other people misuse bits, are making private spaces tough, and not just for celebrities in the glare of publicity's spotlight.
When bad things happen with out-of-control atoms, we respond: we make laws forbidding trains from running red lights, and people from driving drunk. But we're way behind in dealing with bits, and bits are notoriously hard to control with legislation.
Last week, the New York Times published a front-page account that should serve as a cautionary tale for the citizens of our wired world.
An American oil company, the story holds, clobbered a large group of Los Angeles residents first with atoms, then with bits. The company managed to let one of its oil refineries explode catastrophically, bombarding the people living nearby with a week-long torrent of flame, smoke, debris and noxious gas.
Arguably culpable, and facing huge claims for damages, the oil company turned to bits: they gathered reams of data about the claimants and their attorneys - health records, arrest records, welfare and bankruptcy records - and used the information, in at least a few cases documented by the New York Times, to intimidate the claimants and their attorneys.
Smack 'em with atoms, and if that don't get 'em, then bash 'em with bits.
But the bit-bashing could have been as easily prevented as it was easy to do.
Easy to do because the oil company, its attorneys and investigators had very little trouble getting the goods on their litigious opponents. A subspecies of private investigator, known as information brokers, profit by selling information about folks just like you and me.
Some (but not all) information brokers are like digital paparazzi who work out cheap. They will sell you my telephone records for $80, my salary for $75, my bank balance for $190, 10 years of my medical history for $400 and my credit card number for $450.
Not that any of that is likely to do you any good. Even the credit card number would only get you through to the same person who keeps trying to get me to pay off my overdraft.
Information brokers of the species we describe here use lots of questionable methods to gather their data. It's no coincidence that the notorious hacker Kevin Mitnick once had a steady job in the office of a private investigator - and I don't think he was answering phones or going for the doughnuts.
The problem, simply put, has two dimensions:
One, never in the history of civilisation has so much been recorded so routinely about so many. And all that information sits on computers, computers that are often connected to public networks.
Two, the authorities, particularly the American authorities who ride herd over Silicon Valley and other hi-tech geographies, refuse to allow the public access to strong encryption.
If all my records were routinely encrypted, there would be one big, tough, mother-of-all-encrypted-roadblocks in the way of the sleazebags who traffic in this stuff.
Encryption might not stop them completely, but cracking encryption is very expensive - so expensive that even corporate attorneys might think twice about routinely rummaging through people's personal records, looking for a cheap way to take out an opponent.
Making encryption illegal only denies it to the law-abiding citizens. Criminals and others willing to play loose with the law, such as some attorneys and the digital bottom-feeders they support, have the upper hand in a world sans strong encryption.
Ethics and morals may not stop this crowd, but money certainly will.