Is is possible to reason about the (distant) future?

Much of what is written about the medium-to-long-term future is speculative and unconvincing. Is this the best that can be done, or are there methods which provide more soundly based projections into the future?

Its a good idea to think a little first about what you are trying to achieve.

Let's call a method for achieving some purpose rational if it is a good way of going about that end. I am here concerned to distinguish between rational and irrational ways of enquiring into the future.

In general my thinking about the future (at the levels currently under consideration, by constrast with my wondering what the weather might be like tomorrow) is intended to contribute to a contemporary discussion which shapes our conception of what the future might be and what we can do today to steer the ship towards those kinds of future which we consider most desirable.

The ways in which such discussions can shape the future might influence what kinds of thinking it is worth undertaking, so it might be worth thinking this through in greater detail, but in the first instance I will pass over this matter.

I'm going to consider what aspect of the future of humanity will most effectively contribute to the kind of future society I would wish to see.