Complex AI that learns lexical-semantic content and its meaning (such as collection of words, their structure and dependencies) such as Watson takes terabytes of disk space.
Lets assume DeepQA-like AI consumed whole Wikipedia of size 10G which took the same amount of structured and unstructured stored content.
Will learning another 10G of different encyclopedia (different topics in the same language) take the same amount of data? Or will the AI reuse the existing structured and take less than half (like 1/10 of it) additional space?