What Greece & other indebted countries must do

• Default & start from scratch
• Reform society to be agile and economically efficient
• Build trust between people
• Never take loans again

Here's a longer how & why for each one of these:

Default & start from scratch

Being saddled with huge debts is a very bad situation, whether for an individual or family, or for a nation. Over a certain threshold it just becomes impossible. There are examples of countries paying back debts. However a simpler option is to just default. This will also teach creditors to be more careful lending out money in the future.

Reform society to be agile and economically efficient

A society where people can quickly organize and reorganize themselves and their production resources, will have a much smoother ride through times of change. This means low taxes on work, promoting work and division of labor. High taxes kill division of labor since with high taxes it is cheaper to DIY stuff than to outsource it to specialists: For every new person in the chain the tax on wages will take a cut, so with e.g. 50% tax on wages the third person in the chain would receive 25% of what the first person had to earn to pay him. With 30% tax it gets around 50%. So you see how high taxes effectively puts a stop to chains of cooperation.

It must be easy to hire and fire people and to start and scuttle companies. There must be an efficient conflict resolution system. But what if hire and fire creates alienation in society?

Build trust between people

Trust is needed between people to make for a good society. If trust breaks down you will either have anarchy & chaos or a strong leader who oppresses and solves things inefficiently. There are some rather good books about how to start building trust in society by Gene Sharp. Negative income tax or just a guaranteed sum to live from are also interesting ideas. Simple systems are less vulnerable to capriciousness and corruption.

Never take loans again

Loans are probably a bad idea, and should be abolished. This is one of those times when several religions actually got it right. Instead sell equity. With equity in bad times somebody may own what you built but they will not own you. Big difference.