Tim loved his brand new house. The architect, who had supervised the entire building work, designed it so it was a big, open building. The walls were massive windows and the ceiling had a huge skylight in it so the whole house was full of light. There was also a little flowerbed in the middle of it. And in the middle of the flowerbed was one little plant—a gift from the architect himself. The plant would need hardly any attention because the flowerbed had a fully plumbed-in, automated watering system. And, of course, there was plenty of light in the house. All that was required was a little pruning from time to time to keep it from getting out of control.

But Tim's friends weren't so sure about this low-maintenance approach. They encouraged Tim to water it regularly just to make sure, so he did. The magazines Tim read were full of ads for different types of artificial fertilizer recommended for that kind of plant. So Tim tried these too. And the TV gardening programs said it really wasn't a great idea to prune those plants—they needed to be able to grow naturally. So Tim followed that advice too.

And it made a difference. Within weeks, it was shooting up and the leaves were thickening. Soon it was pushing the bounds for a normal-sized houseplant. Tim didn't notice the out-of-proportion growth until the architect came for a visit. When Tim invited him in for a cup of tea he realized just what had happened. By then the change was dramatic. That little plant had started to take over the entire house. Getting around the root structure in the house involved stepping over some branches, ducking others and generally some pretty impressive acrobatics. The plant had come to dominate everything.

But the change which concerned the architect most of all was the lack of light. The foliage was so dense that barely any of that beautiful light was getting through. If you looked really carefully, you could see a kind of pale tinge around the edge of some of the leaves. But that was now about all you could see of the light. It had become a dark green. This was definitely not the architect's original design.