Aww, no alien empires yet

[iancampbell]

It should be noted that the Kardashev Types date from the 60s and may have as much relation to how civilizations actually develop as the imaginings of Jules Verne to with the 21st century we live in.

To take but one factor: A civilization the successfully achieved Zero Population Growth might be hugely advanced - but have no need of things like Dyson Spheres or the like simply because their resource needs are both stable and far below the level where such constructs are required (even if it might be trivial for them to create them if they wished).

The answer to the Fermi Paradox may be something as simple as totally effective birth control and a social model a bit different from our own. It should also be noted that, from our own experience, when you raise people's standard of living and give them access to education - they are less inclined to produce large numbers of children.

I can think of maybe a half dozen scenarios in which alien civs could be relatively common - and not detectable by the methods and models we are using now.

Todd

Your point about birth control and the like is well taken, but we can't know that it applies to all lifeforms. For an example where it doesn't apply because nobody has discovered effective birth control without undesirable side effects, see the Moties.

Another example of a sapient lifeform that wouldn't have the attitudes of humans might be one that produces huge numbers of offspring without investing much in them, and accepts enormous levels of infant mortality - much as Earth organisms such as amphibians and fish do. Sapient frogs wouldn't think like us in this respect - or many other respects, for that matter.