The following is a conversation with Rohit Prasad.

He's the vice president and head scientist of Amazon Alexa and 1 of its original creators.

The Alexa team embodies some of the most challenging, incredible, impactful, and inspiring work that is done in AI today.

The team has to both solve problems at the cutting edge of natural language processing and provide a trustworthy, secure, and enjoyable experience to millions of people.

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This is an important and exciting opportunity.

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And now, Here's my conversation with Rohit Prasad.

In the movie, Her, I'm not sure if you've ever seen it, human falls in love with the voice of an AI system.

Let's start at the highest philosophical level before we get to deep learning and some of the fun things.

Do you think this, what the movie Her shows, is within our reach?

I think not specifically about Her, but I think what we are seeing is a massive increase in adoption of AI assistance or AI and all parts of our social fabric.

And I think it's, what I do believe is that the utility these AIs provide, some of the functionalities that are shown are absolutely within reach.

So some of the functionality in terms of the interactive elements, but in terms of the deep connection that's purely voice-based, do you think such a close connection is possible with voice alone?

It's been a while since I saw her, but I would say in terms of interactions which are both human-like and in these AI assistants, you have to value what is also superhuman.

AI assistants can be in multiple places at the same time.

1 with you on your mobile device, 1 at your home, 1 at work.

So you have to respect these superhuman capabilities too.

Plus as humans, we have certain attributes we're very good at, very good at reasoning.

But in the realm of AI assistants, what they're great at is computation, memory, it's infinite and pure.

These are the attributes you have to start respecting.

So I think the comparison with human-like versus the other aspect, which is also superhuman, has to be taken into consideration.

So I think we need to elevate the discussion

So there's certainly elements, we just mentioned, Alexa's everywhere, computation speaking.

So this is a much bigger infrastructure than just the thing that sits there in the room with you.

But it certainly feels to us mere humans that there's just another little creature there when you're interacting with it.

You're not interacting with the entirety of the infrastructure, you're interacting with the device.

The feeling is, okay, sure, we anthropomorphize things, but that feeling is still there.

So what do you think we, as humans, the purity of the interaction with a smart assistant, what do you think we look for in that interaction?

I think in the certain interactions, I think will be very much where it does feel like a human, because it has a persona of its own.

So I think a simple example to think of it is if you're walking through the house and you just want to turn on your lights on and off and you're issuing a command, that's not very much like a human-like interaction and that's where the AI shouldn't come back and have a conversation with you.

Just, it should simply complete that command.

So those, I think the blend of, we have to think about this is not human-human alone.

is a human-machine interaction and certain aspects of humans are needed and certain aspects and situations demand it to be like a machine.

So I told you it's gonna be philosophical in parts.

What's the difference between human and machine in that interaction?

When we interact to humans, especially those are friends and loved ones, versus you and a machine that you also are close with?

I think you have to think about the roles the AI plays, right, and it differs from different customer to customer, different situation to situation.

Especially I can speak from Alexa's perspective, it is a companion, a friend at times, an assistant, and an advisor down the line.

So I think most AIs will have this kind of attributes and it will be very situational in nature.

I think the boundary depends on exact context in which you're interacting with the AI.

So the depth and the richness of natural language conversation is been by Alan Turing, been used to try to define what it means to be intelligent.

You know, there's a lot of criticism of that kind of test, but what do you think is a good test of intelligence in your view, in the context of the Turing test and Alexa or the Alexa prize, this whole realm, do you think about this human intelligence, what it means to define it, what it means to reach that level?

I do think the ability to converse is a sign of an ultimate intelligence.

I think that there's no question about it.

So if you think about all aspects of humans, there are sensors we have, and those are basically a data collection mechanism.

And based on that, we make some decisions with our sensory brains, right?

And from that perspective, I think that there are elements we have to talk about how we sense the world and then how we act based on what we sense.

Those elements clearly machines have, but then there's the other aspects of computation that is way better.

I also mentioned about memory again, in terms of being near infinite, depending on the storage capacity you have.

And the retrieval can be extremely fast and pure in terms of like, there's no ambiguity of who did I see when, right?

I mean, machines can remember that quite well.

So again, on a philosophical level, I do subscribe to the fact that to be able to converse, and as part of that, to be able to reason based on the word knowledge you've acquired and the sensory knowledge that is there is definitely very much the essence of intelligence.

But intelligence can go beyond human level intelligence based on what machines are getting capable of.

So What do you think, maybe stepping outside of Alexa, broadly as an AI field, what do you think is a good test of intelligence?

Put it another way, outside of Alexa, because so much of Alexa is a product, is an experience for the customer.

On the research side, what would impress the heck out of you if you saw?

You know, what is the test where you said, wow, this thing is now starting to encroach into the realm of what we loosely think of as human intelligence?

So, well, we think of it as AGI and human intelligence all together, right?

So in some sense, and I think we are quite far from that.

I think an unbiased view I have is that the Alexa's intelligence capability is a great test.

I think of it as there are many other proof points, like self-driving cars, game playing like Go or chess.

Clearly requires a lot of data-driven learning and intelligence, but it's not as hard a problem as conversing with as an AI is with humans to accomplish certain tasks or open domain chat, as you mentioned, Alexa Prize.

In those settings, the key difference is that the end goal is not defined, unlike game playing.

You also do not know exactly what state you are in, in a particular goal completion scenario.

Sometimes you can if it is a simple goal, but if you're even certain examples like planning a weekend or you can imagine how many things change along the way.

You look for weather, you may change your mind and you change the destination, or you want to catch a particular event, and then you decide, no, I want this other event I want to go to.

So these dimensions of how many different steps are possible when you're conversing as a human with a machine makes it an extremely daunting problem.

And I think it is the ultimate test for intelligence.

And don't you think that natural language is enough to prove that conversation, just pure conversation?

From a scientific standpoint, natural language is a great test, But I would go beyond, I don't want to limit it to as natural language as simply understanding an intent or parsing for entities and so forth.

So I would say human machine dialogue is definitely 1 of the best tests of intelligence.

you briefly speak to the Alexa Prize for people who are not familiar with it and also just maybe where things stand and what have you learned and what's surprising?

What have you seen that's surprising from this incredible competition?

Absolutely, it's a very exciting competition.

Alexa Prize is essentially a grand challenge in conversational artificial intelligence, where we threw the gauntlet to the universities who do active research in the field to say, can you build what we call a social bot that can converse with you coherently and engagingly for 20 minutes?

That is an extremely hard challenge, talking to someone who you're meeting for the first time, or even if you've met them quite often, to speak at 20 minutes on any topic, an evolving nature of topics, is super hard.

We have completed 2 successful years of the competition.

The first was 1 with the University of Washington, second, the University of California.

We have an extremely strong team of 10 cohorts.

And the third instance of the Alexa Prize is underway now.

It was a lot of things to be put together.

We had to build a lot of infrastructure to enable these universities to be able to build magical experiences and do high quality research.

few quick questions, sorry for the interruption.

What does failure look like in the 20 minute session?

So what does it mean to fail not to reach the 20 minute mark?

So there are 1, first of all, I forgot to mention 1 more detail.

It's not just 20 minutes, but the quality of the conversation too that matters.

And the beauty of this competition, before I answer that question on what failure means, is first that you actually converse with millions and millions of customers as these social bots.

So during the judging phases, there are multiple phases, before we get to the finals, which is a very controlled judging in a situation where we bring in judges and we have interactors who interact with these social bots, that is a much more controlled setting.

But till the point we get to the finals, all the judging is essentially by the customers of Alexa.

And there you basically rate on a simple question how good your experience was.

So that's where we are not testing for a 20-minute boundary being crossed because you do want it to be very much like a clear-cut winner being chosen and it's an absolute bar.

So did you really break that 20-minute barrier is why we have to test it in a more controlled setting with actors, essentially interactors, and see how the conversation goes.

So this is why it's a subtle difference between how it's being tested in the field with real customers versus in the lab to award the prize.

So on the latter 1, what it means is that essentially there are 3 judges and 2 of them have to say this conversation has stalled, essentially.

Got it, and the judges are human experts.

Okay, great, So this is in the third year.

How far, so the DARPA challenge in the first year, the autonomous vehicles, nobody finished in the second year, a few more finished in the desert.

So how far along in this, I would say, much harder challenge are we?

This challenge has come a long way to the extent that we're definitely not close to the 20 minute barrier being with coherence and engaging conversation.

I think We are still 5 to 10 years away in that horizon to complete that.

Like what you're finding is the accuracy and what kind of responses these social bots generate is getting better and better.

What's even amazing to see that now there's humor coming in.

You know, you're talking about ultimate science of intelligence.

I think humor is a very high bar in terms of what it takes to create humor.

I really mean good sense of humor is also a sign of intelligence in my mind and something very hard to do.

So these social bots are now exploring not only what we think of natural language abilities, but also personality attributes and aspects of when to inject an appropriate joke, when you don't know the domain, how you come back with something more intelligible so that you can continue the conversation.

If you and I are talking about AI and we are domain experts, we can speak to it.

But if you suddenly switch a topic to that, I don't know of, how do I change the conversation?

So you're starting to notice these elements as well.

And that's coming from partly by the nature of the 20 minute challenge that people are getting quite clever on how to really converse and essentially mask some of the understanding defects if they exist.

So some of this, this is not Alexa the product, this is somewhat for fun, for research, for innovation and so on.

I have a question, sort of in this modern era, there's a lot of, if you look at Twitter and Facebook and so on, there's discourse, public discourse going on and some things are a little bit too edgy, people get blocked and so on.

I'm just out of curiosity, are people in this context pushing the limits?

Is anyone sort of pushing back, sort of, you know, arguing, I guess I should say, as part of the dialogue to really draw people in.

First of all, let me just back up a bit in terms of why we are doing this, right?

I think fun is more part of the engaging part for customers.

It is 1 of the most used skills as well in our skill store.

But up that apart, the real goal was essentially what was happening is with a lot of AI research moving to industry, we felt that academia has the risk of not being able to have the same resources at disposal that we have, which is lots of data, massive computing power, and clear ways to test these AI advances with real customer benefits.

So we brought all these 3 together in the Alexa Prize.

That's why it's 1 of my favorite projects in Amazon.

And with that, the secondary effect is, yes, it has become engaging for our customers as well.

We're not there in terms of where we want it to be, right?

But coming back to your question on how do the conversations evolve?

Yes, there is some natural attributes of what you said in terms of argument and some amount of swearing.

The way we take care of that is that there is a sensitive filter we have built.

It's more than keywords, a little more in terms of, of course, there's keyword-based too, but there's more in terms of, these words can be very contextual, as you can see, and also the topic can be something that you don't want a conversation to happen, because this is a communal device as well.

So we have put a lot of guardrails for the conversation to be more useful for advancing AI and not so much of these other issues you attributed, what's happening in the AI field as well.

Right, so this is actually a serious opportunity.

I think it's an open opportunity to do some of the best innovation and conversational agents in the world.

Young minds, it's also to, if you think about the other aspect of where the whole industry is moving with AI, there's a dearth of talent given the demands.

So you do want universities to have a clear place where they can invent and research and not fall behind, but that they can't motivate students.

Imagine all grad students left to industry, like us, or faculty members, which has happened too.

So this is a way that if you're so passionate about the field where you feel industry and academia need to work well, this is a great example and a great way for universities to participate.

YARO So what do you think it takes to build a system that wins the Alexa prize?

KUMAR I think you have to start focusing on aspects of reasoning, that it is, there are still more lookups of what intents the customer is asking for and responding to those, rather than really reasoning about the elements of the conversation.

For instance, if you're playing, if the conversation is about games and it's about a recent sports event, there's so much context involved and you have to understand the entities that are being mentioned so that the conversation is coherent rather than you suddenly just switch to knowing some fact about a sports entity and you're just relaying that rather than understanding the true context of the game.

Like if you just said, I learned this fun fact about Tom Brady, rather than really say how he played the game the previous night, then the conversation is not really that intelligent.

So you have to go to more reasoning elements of understanding the context of the dialogue and giving more appropriate responses, which tells you that we are still quite far, because a lot of times it's more facts being looked up and something that's close enough as an answer, but not really the answer.

So that is where the research needs to go more, an actual true understanding and reasoning.

And that's why I feel it's a great way to do it because you have an engaged set of users working to make, help these AI advances happen in this case.

You mentioned customers there quite a bit, and there's a skill.

What is the experience for the user that's helping?

So just to clarify, this isn't, as far as I understand, the Alexa, so this skill is a standalone for the Alexa prize.

It's not you ordering certain things on Amazon.com or checking the weather or playing Spotify, right?

I don't know, how do people, how do customers think of it?

And let me tell you how you invoke the skill.

So all you have to say, Alexa, let's chat.

And then the first time you say, Alexa, let's chat, it comes back with a clear message that you're interacting with 1 of those university social bots.

And there's a clear, so you know exactly how you interact, right?

And we have a lot of mechanisms where as the, we are in the first phase of feedback phase, then you send a lot of emails to our customers and then they know that the team needs a lot of interactions to improve the accuracy of the system.

So we know we have a lot of customers who really want to help these university bots, and they're conversing with that.

And some are just having fun with just saying, Alexa, let's chat.

And also some adversarial behavior to see whether, how much do you understand as a social bot.

So I think we have a good healthy mix of all 3 situations.

So what is the, if we talk about solving the Alexa challenge, the Alexa prize, What's the data set of really engaging pleasant conversations look like?

Because if we think of this as a supervised learning problem, I don't know if it has to be, but if it does, maybe you can comment on that.

think there needs to be a data set of what it means to be an engaging, successful, fulfilling conversation?

I think that's part of the research question here.

This was, I think, we at least got the first part right, which is have a way for universities to build and test in a real world setting.

Now you're asking in terms of the next phase of questions, which we are also asking, by the way, what does success look like from a optimization function?

That's what you're asking in terms of, we as researchers are used to having a great corpus of annotated data and then making, then sort of tune our algorithms on those, right?

And fortunately and unfortunately, in this world of Alexa Prize, that is not the way we are going after it.

you have to focus more on learning based on live feedback.

That is another element that's unique where just now, I started with giving you how you ingress and experience this capability as a customer.

So they ask you a simple question on a scale of 1 to 5, how likely are you to interact with this social bot again?

That is a good feedback and customers can also leave more open-ended feedback.

And I think partly that to me is 1 part of the question you're asking, which I'm saying is a mental model shift that As researchers also, you have to change your mindset that this is not a DARPA evaluation or a NSF funded study and you have a nice corpus.

This is where it's real world, you have real data.

And then the customer, the user can quit the conversation at any time.

That is also a signal for how good you were at that point.

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Rohit Prasad: Amazon Alexa and Conversational AI | Lex Fridman Podcast #57