# THE PRINCIPLE OF MULTIPLE USE
Viable systems show a preference for products and processes by which they can kill two (or even more) birds with one stone, a variation of the **Jiu-Jitsu theme**.
🔴 What we create or do should serve more than one purpose at a time.
Multiple use also means solving problems with several partial solutions and not with one 100 % solution (which implies that a failure also means a 100 % failure).
In housing energy systems, for example, a mix of energy boxes, ambient heat from the ground, biogas from waste, water purification, composting, and a biotop roof - each of them even serving several purposes - can be combined to one complex system.
In case one solution fails, the rest still works: the system shows multistability.
# Multiple use Multiple utilization of products, functions and organizations.
**Precondition:** Diversity of system components, small scaled system structure.
>This seems like two very different concepts. Multi use creates large cascades of benefit and failures. The other concept seems to be modularity and backup systems which fails back more gracefully that simple chains or strict network cascades.