Please define "packed" with cars. What percentage of all trips taken by private car counts as "packed"?

I mean, Copenhagen and Amsterdam manage 33-40% of all trips taken being by private car, compared to 80-90% for Aussie and US cities. Now, maybe you'd call 33-40% of all trips "packed"; but you must agree that this is less "packed" than Melbourne or Detroit.

If we could go from 80-90% to to 33-40%, we'd use only one-third to one-half the fuel for private transport we now do. Which is just what I said earlier, that individuals and cities as a whole could without a great deal of trouble halve their fuel use.

Now, I think we can and will have to get below that level in the long run - the next few decades. But it'd be a bloody good start. If such efficiencies were carried out across the economy we could be self-sufficient in oil, close down half our coal-fired stations, save billions on new highways, halve our total carbon emissions, and so on.

If you accept that most people have a need for a car, beyond what can be provided even by the best mass-transit,

No, I don't accept it, because it's not true. Most Aussies and Americans have the desire for a car, and are accustomed to having and using one, but considerably fewer need a car.

Of course, when you tell me that you need to travel 1km to the shops by car, we could be using different definitions of the words "need" and "necessary". I suggest we use the words as commonly understood, as expressed by the dictionary.

necessary, noun

# absolutely essential
# unavoidably determined by prior circumstances; "the necessary consequences of one's actions"
# necessity: anything indispensable; "food and shelter are necessities of life"; "the essentials of the good life"; "allow farmers to buy their requirements under favorable conditions"; "a place where the requisites of water fuel and fodder can be obtained"

As the figures show, only about one-third of trips are unavoidable (assuming utterly unwalkable and unbikable neighbourhoods, and zero public transport - a wrong assumption, but let's be generous to the "needy"); about two-thirds of all trips taken by car are discretionary or could be rolled together with other trips. In my "immodest proposal" article I suggested that everyone keep a logbook in their car and for a month write down every trip and for what purpose it was taken, and after that month sit down and have a look to see if the trip was necessary, could have been bundled with another, or taken by foot, cycle or public transport without great inconvenience. I don't know of anyone having actually accepted the challenge, though.

Perhaps they were worried at what results they might get.

There's a difference between what's necessary and what we're accustomed to. You're accustomed to driving 1km to the shops; but if your car broke down, you would presumably not go without food because the journey is impossible to take by other means. It's simply that you're accustomed to doing this.

I understand. For my part, I only got my driver's license recently, so that whenever I have to travel somewhere I get out the map and the train and bus timetables. And occasionally my woman says to me, "it'd be easier to take the car, you know." And I say, "oh... I hadn't thought of that." It simply hadn't occurred to me that the car was an option, because I'm accustomed to walking and public transport. Likewise, long-term car drivers, it simply doesn't occur to them to walk or use public transport, because they're accustomed to driving.

Custom thus becomes a "need". When people's customs in travel, in diet and lifestyle are challenged, they often assert "need", insisting that things must be this way. But in fact there are a zillion ways to live your life, and if you just get your caca together you can change the way you do things.

You cannot really expect the government to pass radical laws about carbon taxes or trades and invest billions in public transport and renewable energy if you will not even make the enormous, painful and stressful effort to walk 1km to the shops.