Cheyer explains Viv like this. Imagine you need to pick up a bottle of wine that goes well with lasagna on the way to your brother's house. If you wanted to do that yourself, you'd need to determine which wine goes well with lasagna (search #1) then find a wine store that carries it (search #2) that is on the way to your brother's house (search #3). Once you have that figured out, you have to calculate what time you need to leave to stop at the wine store on the way (search #4) and still make it to his house on time.

[…] But how can simple code assimilate something as complex as speech in only the span of a handful of years? It took humans hundreds of generations to identify, compose and collate the English language. Chatbots have a one up on humans, because of the way they dissect the vast data given to them. Now that we have a grip on the basics, we’ll understand how chatbots work in the next series. […]
Jabberwacky learns new responses and context based on real-time user interactions, rather than being driven from a static database. Some more recent chatbots also combine real-time learning with evolutionary algorithms that optimise their ability to communicate based on each conversation held. Still, there is currently no general purpose conversational artificial intelligence, and some software developers focus on the practical aspect, information retrieval.

ETL. The bot relies on information and knowledge extracted from the raw data by an ETL process in the backend. This data might be structured (SQL database), semi-structured (CRM system, FAQs), or unstructured (Word documents, PDFs, web logs). An ETL subsystem extracts the data on a fixed schedule. The content is transformed and enriched, then loaded into an intermediary data store, such as Cosmos DB or Azure Blob Storage.
“There is hope that consumers will be keen on experimenting with bots to make things happen for them. It used to be like that in the mobile app world 4+ years ago. When somebody told you back then… ‘I have built an app for X’… You most likely would give it a try. Now, nobody does this. It is probably too late to build an app company as an indie developer. But with bots… consumers’ attention spans are hopefully going to be wide open/receptive again!” — Niko Bonatsos, Managing Director at General Catalyst
[In] artificial intelligence ... machines are made to behave in wondrous ways, often sufficient to dazzle even the most experienced observer. But once a particular program is unmasked, once its inner workings are explained ... its magic crumbles away; it stands revealed as a mere collection of procedures ... The observer says to himself "I could have written that". With that thought he moves the program in question from the shelf marked "intelligent", to that reserved for curios ... The object of this paper is to cause just such a re-evaluation of the program about to be "explained". Few programs ever needed it more.[8]