I have learned the hard way, as father to three small boys, that sharing causes conflict. Ask humans to play with the same toy at the same time, and it won't take long for a fight to break out. The smart move is to find duplicates of that toy, or to urge interested parties to "take turns."
That's why I fear the much-celebrated "sharing economy" - the catch-all name for "peer-to-peer" firms, many based in California, that connect people for the purposes of distributing, sharing and reusing goods and services - is likely to produce more fights than profits. And that would embroil our state in political, legal, commercial and environmental battles.
I hope I'm wrong about this. Companies such as the ride-sharing services Lyft and Uber and the apartment-sharing service Airbnb are California success stories. Sharing services can eliminate waste, improve efficiency, connect people to one another and allow us to make money on extra stuff in our closets and garages.
If that's all the sharing economy promised to do, I'd have no reason to worry. But the sharing economy is more than a business sector, it's a movement, with the grandest of ambitions for our politics, culture and environment.
Over a couple of months of reading about and talking to people in the sharing economy, I've been struck by the limitless aspirations of its participants and proponents. Here are just a few: reversing economic inequality, stopping ecological destruction, countering materialism and capitalism, enhancing worker rights, empowering the poor and reimagining our politics.
It would be easy to dismiss this as just more of the self-aggrandizing, self-righteous nonsense for which liberal pockets of California are well-known. Except that the sharing economy is already threatening to reach into every corner of our lives, food to photography, education to finance.
If that sounds like an exaggeration, consider this: Venture capitalists just funded an app to help you find someone to do your laundry for you.
In this context, my bid to watch your dog while you're on vacation - and yours to drive me to the airport - are at once freeing and full of dangers. Who's responsible if your dog bites my kid while in my care? What kind of car insurance, training and licensing do you need to shuttle me safely? What, if anything, do we owe to the kennel workers and cabbies who lose work? And who governs all of this?
There are so many potential conflicts posed by sharing - along professional, political, commercial, geographic, generational, and gender lines - that I couldn't list them here. To pick just one more: Sharing is a threat to the general plans of virtually every city. After all, what is Airbnb if not rezoning residential areas into hotel space?
Of course, the movement doesn't see itself as a starter of wars - and that may be its biggest weakness. Instead of recognizing the conflict and anger that could be produced by their efforts to transform the world, cheerleaders of the sharing economy celebrate its "disruptive" power, as well as its "sustainability."
Whether used by the environmental left or the anti-spending right, "sustainability" has become a vague if powerful way to dismiss somebody else's idea without having to reckon with the particulars. "That's unsustainable," means it can't go on, so why continue to discuss?
These days, it's how we say "no" to anything new that might cost money or consume energy. So, naturally, almost every government or corporate bureaucracy you encounter in California has an office of sustainability.
What California doesn't have is the governance infrastructure to sort out the multifront battles over sharing and sustainability that are on the horizon. California's weak local governments can't deal with all the new planning, zoning, licensing and regulatory questions posed by this new economic model. The state's courts are already too crowded to handle basic functions - much less a host of new claims sparked by sharing enterprises. And our political system, with its low voter participation and big money, simply can't produce definitive, legitimate answers on the big new policy questions posed by all this sharing.
For all its promise, the sharing economy threatens to turn virtually every aspect of living in California into contested ground. And that's no way to live.
Joe Mathews writes the Connecting California column for Zócalo Public Square.