The Night Sessions

I've read The Star Fraction, and The Night Sessions is even better. Macleod's powers seem to be waxing. I'm always pleased when someone gets better with age, it gives me a little hope. There's humour and humanity in this book. Compared to The Star Fraction, I feel that this is a more confident work. As John Major would say, an author at ease with himself.

I like the way that the humans and robots co-exist as equals in their work as detectives. Though the problem is that by that stage in real life, the robots would have overtaken us and we would either have to augment ourselves or become irrelevant.

Talking of increased intelligence can someone tell me in detail what humankind's history would have been if our intelligence had been located in our fat, rather than in our brains? That is, if you got fatter, you got more intelligent. What would happen then?