(2022-04-04) Brander Stepping Stones In Possibility Space

Gordon Brander: Stepping stones in possibility space. In Possibility Space, we looked at the creative process as a search problem, an exploration through the space of possibility

This cavernous room is the space of all possible images

but it also contains a lot of noise. How best to navigate this possibility space? How do we get to the good stuff?

AI researchers Kenneth Stanley and Joel Lehman explore exactly this challenge through their work on Novelty Search algorithms. In their book, Why Greatness Cannot Be Planned (2015), and in their published research, they offer many insights into how we might effectively navigate possibility space

one common strategy for navigating possibility space is the warmer-colder game

This challenge of navigating discontinuous possibility spaces is not uncommon. In fact, it turns out that many possibility spaces are discontinuous. Take the history of computing. It is full of discontinuities:

For the warmer-colder game to work, you need a neatly organized possibility space. If you can travel in the direction of more

discontinuities are not a fluke in the history of computing. It seems discontinuities are the rule, rather than the exception. Breakthroughs come from unexpected directions. Reality itself is a discontinuous possibility space!

In such a situation, objectives are worse than useless. They get you stuck.

Stanley and Lehman offer us a thought experiment. Imagine a lake. Scattered across the surface of this lake are stepping stones.

What are these stepping stones? They are strategies within the possibility space that have been found to work—or as evolutionary philosopher Daniel Dennett puts it—good tricks for survival. Vacuum tubes, clock-making, weaving, semiconductor physics, and the exploration of mathematics for religious reasons were all unexpected stepping stones in the evolution of modern computing.

What does?

If we try to cross this lake by following only the stepping stones that lead toward our objective, we’ll soon get stuck. But what if we let go of our objectives? What if we focused on trying to find new stepping stones instead? This is novelty search. Instead of looking for something specific, you look for something new. (interestingness)

Stepping stones are also combinatorial.

What if we reimagine note-taking through this lens? Every note you take is a stepping stone, expanding your combinatorial space of possibility.

In fact, evolution itself is a kind of non-objective search, in the same family of algorithms as novelty search.