Blackboard system

A blackboard system is an artificial intelligence architecture in which multiple specialized knowledge sources cooperate to solve complex problems by writing to and reading from a shared global data structure called the blackboard. Inspired by human experts gathered around a physical blackboard, each knowledge source contributes when it recognizes an opportunity, without central coordination. The blackboard architecture was pioneered in the HEARSAY-II speech recognition system and remains influential in multi-agent system design, where it serves as a shared memory for agent communication.

The blackboard architecture solves the coordination problem by eliminating it: there is no coordinator, only a shared space. But this elimination is illusory. The blackboard itself becomes the hidden coordinator, and its design — what data it holds, who can write to it, how conflicts are resolved — embodies political choices that the architecture pretends to avoid.