Traditional blockchains and client/server systems start from a data-centric ontology. They are built around the concept that data is a ‘thing’ that exists in and of itself apart from any observer.
An agent-centric ontology views data as a perspective or an observation shared by multiple individuals. We believe this is the way the real world works: both Einstein and quantum physicists assert that physical phenomena are relative to the context of the observer. Variances in observations indicate that there is no one, reliable, objective reality.
This may all seem too theoretical, but we can even observe this in daily life. What is the temperature of the room around you? The thermostat on the wall records one temperature, the thermometer stuck on the window and bathed in full sunlight records another, the decorative thing your aunt gave you is wildly miscalibrated, and your nose feels cold. There’s no one true room temperature, only a set of perspectives.
This also has serious implications for how a distributed system is built. When faced with the objective truth about subjectivity, you have choices to make. Client/server chooses to accept one perspective as canonical and throw away all other perspectives. Blockchain does the same thing, expending a lot of energy getting everyone to agree on that perspective. But Holochain allows each agent to record their own perspective, only expending energy on consensus where it matters — among the agents who actually care about the data they’re trying to agree upon. This avoids the power concentration of client/server and the inefficiency of blockchain.
Using tech that embodies an agent-centric mindset also enables vastly richer interactions and collaboration. All perspectives are preserved and come together to form a more comprehensive picture of the whole.