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Hello everyone. In this video, we're
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going to try to address the question of
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what is AI? In fact, there are many
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definitions for AI systems. But these
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various definitions can fall under one
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of four different categories. The first
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category says that AI systems are
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systems that try to think like humans.
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Of course, these are involved with
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trying to understand how humans think.
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The other set of definitions is involved
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with or they define AI systems as
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systems that act like humans and these
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are involved with understanding human
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behavior, how humans behave. The third
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category of definitions focuses on how
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to think rationally. They say AI systems
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are systems that kind of think
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rationally. And of course this is
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involved with the question of okay how
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do we make rational decisions and how do
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we define rationality in the first
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place. Now the last category of
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definitions is focused on acting
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rationally. They say that AI systems are
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systems that are able to act rationally
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meaning how to act rationally in order
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to achieve a certain goal. Okay. Now
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let's take a look at each of these set
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of definitions. If we try to focus on
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systems or if we define AI as systems
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that try to think like humans then we
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need to understand how humans think.
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This knowledge is will take us to things
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like neuroscience and cognitive science
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that basically try to understand how the
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human brain works and how the thinking
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process takes place. As for definitions
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that rely on acting like human or
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behaving like human, well, in that case,
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we need to understand human behavior and
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that kind of depends on psychology.
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But Alan Turan actually came out with a
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test that allows us to evaluate an AI
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system and whether it does act like
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humans or not. His test is very simple.
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He basically said, okay, let's have some
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sort of an interrogator. First of all,
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you can imagine that this AI system is
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something like a chatbot. Okay? And now
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a human interrogator is interacting with
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this chatbot. If this human is unable to
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to figure out whether this is a bot or
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an actual human that is chatting with
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him or her, then we would say that this
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AI system has passed the Turing the
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Turing test and we can say that it is
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So in order of course for an AI system
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to be able to act like humans, it needs
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to understand multiple things
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to understand natural language
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processing because it will interact with
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humans, right? So it has to have a way
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to process this natural language and use
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it to represent knowledge and also has
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to have a mechanism to reason about this
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knowledge, process it somehow. And it
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needs of course means for machine
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>> in order to learn something and
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eventually respond to this human.
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Now, as for thinking or focusing on
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thinking rationally, now we need to
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define what is rational thinking. Of
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course, this is a philosophical
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question, right? and Aristotle was the
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first to try to address it and that led
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him to the development of logic and the
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inference rules that we can use in order
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to infer correct results whenever we are
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given correct premises.
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Okay. So let me give you an example. So
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if we have two premises like this, if we
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say you know what Socrates is a man and
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all men are mortal, then from these two
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premises we can infer or conclude that
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Socrates is mortal. Okay.
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Now, of course, trying to answer the
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question of what is rational thinking is
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something that usually philosophers or
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people that belong to different moral
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value systems would be concerned with.
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But in AI systems, we try to use the
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same terminology that is used in
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but we give it very specific measurable
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definitions. Okay? Okay. So, this is
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just something to keep in mind as we go
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forward because we will be using terms
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that normally humans do it to represent
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or to describe human behavior. We're
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going to use it to describe the behavior
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of these AI systems, but they don't
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necessarily mean the same thing. It's
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like a very watered down version of of
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the same definition of the same word.
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Okay. Now moving to the last set of
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definitions that relies on acting
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rationally. Well again we need to define
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what is rational behavior. In fact we
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define in AI we define rational behavior
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with respect to or in terms of a given
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goal. We say that rational acting leads
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to achieving the best possible outcome.
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And as you can see this definition, the
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way we define rational acting over here
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is very different from the way a philos
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a philosopher would uh define the same
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term. Okay. So again we are using very
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specific definitions of something that
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maybe in philosophy people keep fighting
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about okay what is the correct
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definition but over here in AI we try to
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make everything measurable and
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quantifiable. So again rational behavior
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is defined in terms of trying to achieve
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a certain goal. A rational acting is
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going to lead to achieving this goal or
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achieving the best possible outcome.
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Sometimes the goals are very complex.
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They have different components. So we
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are at least trying to achieve the best
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possible outcome and that would be what
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we call rational acting or behavior.
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Now, as you can see, all of these
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borrow information from different
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disciplines and sciences. Like trying to
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think like humans, well, we have to
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understand how humans think, how the
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brain works. And this borrows
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information from neuroscience.
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Trying to have AI systems to act like
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humans. This will need to borrow
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information from psychology because this
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is where we study how humans behave,
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right? Thinking rationally borrows
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information from logic and acting
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rationally borrows information from
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economics because how can you measure
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whether you have reached a goal or not?
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Especially if you have uncertainty in
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the environment around you and if the
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goal is complex and it contains multiple
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different components that may kind of
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oppose each other. Okay. Now, AI systems
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also depend on math in order to try to
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quantify the goals that we're trying to
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reach and how to measure the extent by
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which we have reached these goals. Of
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course, it borrows or it relies on
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computer engineering in order to build
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the hardware of these AI systems. It
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borrows information from linguistics in
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order to enable these AI systems to some
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somehow process natural language. I
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don't want to use the word understand
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human language because understanding is
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a debatable term itself. What do we mean
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by understanding? But we can say AI
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systems should be able to process
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natural language in some way. [snorts]
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And AI systems also rely on control
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theory because these AI systems or
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agents should control themselves and
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have some control over the environments
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So to wrap up, there are actually many
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definitions of AI. All of them rely on
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theories that come from other
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disciplines as we just
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saw and the most common approach to AI
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actually leans off definitions that
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relate it to rational acting. Okay. So
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modern AI focuses on definitions that
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relate AI systems to how to act
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rationally in order to achieve a
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specific goal or maximize the outcome.
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Now AI actually requires a lot of things
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and it borrows information from a lot of
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things but these are the main very basic
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things that AI requires. Some way to
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process natural language. Some methods
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to represent human knowledge and to be
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able to reason about it to infer new
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information from the information and the
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knowledge that we already possess.
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should be able to reason under certainty
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and uncertainty because sometimes we do
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not have full knowledge actually most of
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the time in most complex AI systems we
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do not have full knowledge right so
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there's a notion of uncertainty that is
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going on AI systems requires an ability
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to allow the machines to learn new
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patterns and use them to enhance their
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and AI systems require a form of
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perception and action or acting that
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utilize izes computer vision and
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robotics simply because these AI systems
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they interact with the environment
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around them. Again the term perception
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is in AI systems is used to mean
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something that is kind of relevant to
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human perception of the environment but
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it's not the same. So basically AI
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systems requires means to take input
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from the environment okay and process it
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somehow through computer vision and it
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should also be able to act upon the
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environment through means of robotics
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and things like that that allow it to
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achieve its goal if its goal needs that.
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So that's pretty much it. This was a
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quick summary that tries to answer the
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question, what is AI and what are the
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different categories of definitions for
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AI systems and the main set of
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definitions that modern AI relies on
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which is trying to create systems that
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act or behave rationally. Thank you.