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 \newpage
 
 \section{Introduction}
+This first section is dedicated to defining the core concepts that will be developed in the course. Most importantly, the definitions of what is an intelligent system/machine.
 
-\begin{definition}{Artificial Intelligence}
-    plop
+\begin{definition}{Intelligent System}
+    An algorithm enabled by constraints, exposed by representations that support models, and targeted at reflection, perception, and action.\\
+    Without loss of generality, an intelligent system is one that generate hypotheses ans test them.
 \end{definition}
 
+We say that the algorithm is \textit{enabled by constraints} because the constraints gives it a direction to follow to solve the problem. Without constraints, the fields of possible solutions is too broad and the algorithm cannot posible start choosing a direction. The constraints are necessary to enable the intelligence. An intelligent system has one main feature that is the generation of outputs based on the inputs and the nature of the system. Common capabilities of inteligent systems include sensory perception, pattern recognition, learning and knowledge acquisition, inference from incomplete information etc.
+
+\begin{definition}{Intelligent Machine}
+    An intelligent machine is one that can exibit one or more intelligent characteristics of a human. An intelligent machine embodies machine intelligence. An intelligent machine, howevern may take a broader meaning than an intelligent computer.
+\end{definition}
+
+\begin{figure}[h]
+    \centering
+    \includegraphics[width=0.8\textwidth]{images/intelligent_machine_example.png}
+\end{figure}
+
+
 
 
 \end{document}