# Life time

Almost opposite approaches:

**Traditional computation**:- Produce correct answers, quickly if possible.
**Living computation**:- Produce timely answers, correctly if possible.

Life’s decisions usually can’t be deferred forever, but they aren’t always needed immediately either.

They are needed when they’re needed, as dictated by the situation. But most computing is ill-preparedChess playing programs that manage their own timekeeping are one exception. to exploit such temporal environments.

*Computability theory* doesn’t care a whit how long a
computation would take, only whether it’s possible or not.

Wait, it *really* doesn’t care about time? Yep, it really
doesn’t: Take a millisecond or take a millenium, it’s all the same to
computability theory.

And that reality distortion field powers proofs of ‘universality’ and ‘computational equivalence’ dating from the originals like Turing, Church, and Gödel to more recent writingSo a cellular automaton is equivalent to a brain, when the age of the universe is equivalent to a coffee break..

*Computational complexity*, on the other hand, *does*
care how much time and space things take to compute. For
computational complexity, faster and smaller is always better.

But between or bestride or beyond computability theory and computational complexity, there is precious little theory of how best to solve problems given, say, one whole second using a computer the size of, say, one whole brain.

Life is deadline-drivenit seems to me, as I write this early on a Tuesday morning…, if sometimes the deadlines aren’t completely crisp and sometimes what is available and required isn’t completely clear either.

Estimating the *urgency* of a situation, how much computation
time remains; judging whether to ‘cash out’ with one’s current best
answer, or try to find a better one…

Computers today absolutely suck at these things.

Try your hand on this little model (new window); an abstract lifetime in a box:

What’s right about this model? What’s its biggest flaw? Discuss.