% (find-angg "LATEX/2017puc-abstract.tex")
% (defun c () (interactive) (find-LATEXsh "lualatex -record 2017puc-abstract.tex"))
% (defun d () (interactive) (find-xpdfpage "~/LATEX/2017puc-abstract.pdf"))
% (defun e () (interactive) (find-LATEX "2017puc-abstract.tex"))
% (defun u () (interactive) (find-latex-upload-links "2017puc-abstract"))
% (find-xpdfpage "~/LATEX/2017puc-abstract.pdf")
% (find-sh0 "cp -v  ~/LATEX/2017puc-abstract.pdf /tmp/")
% (find-sh0 "cp -v  ~/LATEX/2017puc-abstract.pdf /tmp/pen/")
%   file:///home/edrx/LATEX/2017puc-abstract.pdf
%               file:///tmp/2017puc-abstract.pdf
%           file:///tmp/pen/2017puc-abstract.pdf
% http://angg.twu.net/LATEX/2017puc-abstract.pdf
%
% https://mail.google.com/mail/ca/u/0/#sent/15bfa10172153bfd
%
\documentclass[oneside]{book}
\usepackage[colorlinks]{hyperref} % (find-es "tex" "hyperref")
\begin{document}

\noindent
{\bf Intuitionistic Logic (and Planar Heyting Algebras) for Children}

\noindent
Eduardo Ochs - UFF (Rio das Ostras)

\bigskip

In this talk we will see a way to interpret Intuitionistic Logic {\sl
visually}.

One great way to make the expression ``for children'' precise in
mathematical titles is to define ``children'' as ``people without
mathematical maturity'', in the sense that they are not able to
understand structures that are too abstract straight away --- they
need particular cases first.

The structures in which we can interpret operations like `and', `or'
and `implies' and they obey the rules of intuitionistic logic are
called Heyting Algebras. It turns out that finite, planar Heyting
Algebras (``ZHAs'') can be drawn as subsets of rectangles, and we will
see how the operations `and', `or' and `implies' can be calculated
visually on them, and why they have to behave in that way. We will
also see how ZHAs can be a tool for understanding Heyting Algebras in
general and several other related concepts, like deduction trees,
simply typed lambda-calculus, and categories.

(Note: this material has been tested on real children --- young
Computer Science students! --- and they liked it a lot)

\bigskip

Paper, slides and links:

\url{http://angg.twu.net/math-b.html#ebl-2017}

\url{http://angg.twu.net/math-b.html#zhas-for-children-2}

\end{document}

% Local Variables:
% coding: utf-8-unix
% End:

