clarifying the description of pi_2 and the fundamental 2-groupoid; al…

…so testing commit from sagemath
kim-em · Feb 22, 2017 · 18e5a4a · 18e5a4a
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diff --git a/.gitignore b/.gitignore
@@ -1,4 +1,5 @@
 *.aux
 *.fdb_latexmk
 *.fls
-*.log
+*.log
+*.synctex.gz
diff --git a/notes/week-1/2017-02-22_algebraic-topology.pdf b/notes/week-1/2017-02-22_algebraic-topology.pdf
diff --git a/notes/week-1/2017-02-22_algebraic-topology.tex b/notes/week-1/2017-02-22_algebraic-topology.tex
@@ -139,7 +139,7 @@ \section{The Second Homotopy Group}
 \end{enumerate}
 \end{defn}
 
-Then $\pi_2$ is a piece of the fundamental 2-groupoid: restrict the 0-layer to just one point, then take the resulting 2-layer.
+Then $\pi_2$ is a piece of the fundamental 2-groupoid: restrict the 0-layer to just one point (the basepoint), restrict the 1-layer to just the constant path at that point, and then take all the `paths of paths` from that constant path to itself. This is just a different way of talking about maps of $S^2$ to the space.
 
 \section{CW-complexes}