Dear Saltpetre,

From death comes life. Our ancestors mostly are dead. We rarely have ancestors more than one or two generations back alive. However, we carry them in our genes. We carry their attitudes in our behaviour.

We carry the 369 degree circle, the 60 second minute, the 60 minute hour, the invention of gods, democratic assemblies, chosen people, the wheel, domesticated animals and other ideas and social forms from the societies and people who have first thought of these things. Our societal forms, customs and knowledge are inherited from the past. Added to that is what we are developing today.

Just as my physical being is the product of the physical beings of my ancestors minus the genes of my ancestors that were not transmitted some of the social developments of the past is lost. My wife and I speak English predominately, but several generations back none of our ancestors spoke English. Going back further in time the English language did not exist. We exist in a world of change. From death comes life.

david f,

I love the way you are always talking about the Arts things like history, archaeology, anthropology, sociology, philosophy, etc.

If I didn't know you were a mathematician I would swear you were a sociologist, anthropologist, historian, or someone else with an Arts background.

I suppose it is just a case of you knowing that no one is interested in hearing you talk about Laplace transforms, multivariable calculus, etc.

Due to our limited water resources cotton should not be grown in Australia.

This is interesting maths...

http://en.wikipedia.org/wiki/Cayley%E2%80%93Dickson_construction

david f,

It's not just a water problem in Australia that we have to worry about,

Very few areas of the country have fertile soils (geologically speaking). Most of the land is sandy soils where the nutrients in the soil are provided by the sparse vegetation.

Several years of intensive agriculture, in all but a few places that are blessed eg Wheat Belt in SW WA, results in overexploitation and environmental degradation of the land.

So the problem is more complex than just the water issues.

Large-scale irrigation results in salination, making the land useless for farming similar to what happened in ancient Mesopotamia. The only way to get rid of the salt is by intensive flushing with water. This is definitely a problem because we don't have a constant reliable source of water in the M-D Basin.

So I definitely agree with you that cotton should not be grown in Australia. But try to telling that to the Chinese because they're the ones doing it!

Canem Malum,

I did a lot of maths when I did my engineering degree and loved it but today it scares the sh!t out of me.