Nupic showcases it's "What did the fox eat" use case which uses cortical.io's SDRs of words. In this example it "asks the question" what does the fox eat after teach it what other animals eat, and without ever seeing fox before, it's able to accurately say what it eats since it groups foxes with coyotes, etc, which have a similar SDR. However, this is a sequence... They fed it sentences only in the form "a eats b" and then fed it "fox eats", and it replied "rodent" or whatever... The SDR's have to be sequences in order for the HTM to work. So if you ask "Guess how many balls are in this jug", you have to do an implied computation to guess how many possible balls fit inside the jug, and that implied computation is not the word sequence (or sdr sequence). Even if you gave it an infinite amount of similar questions and answers like this, it would never be able to figure out a general way to answer the question, which means you could always stump it by giving a different sized jug + different sized ball.