ptolemaicastronomy (6apr19)

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diff --git a/Master/texmf-dist/doc/latex/ptolemaicastronomy/README.md b/Master/texmf-dist/doc/latex/ptolemaicastronomy/README.md
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+ptolemaicastronomy
+==================
+
+Diagrams of sphere models for variably strict conditionals (Lewis
+counterfactuals)
+
+Author: Richard Zach
+E-mail: rzach@ucalgary.ca
+License: Released under the LaTeX Project Public License v1.3c or later
+See: http://www.latex-project.org/lppl.txt
+
+David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+semantics for counterfactual conditionals. He jokingly referred to the
+diagrams depicting such sphere models as Ptolemaic astronomy, hence
+the name of this package. It has nothing to do with Ptolemy or with
+astronomy, sorry.
+
+The macros provided in this package aid in the construction of
+sphere model diagrams in the style of Lewis. The macros all make use
+of TikZ.
+
+See https://github.com/rzach/ptolemaic-astronomy
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/Master/texmf-dist/doc/latex/ptolemaicastronomy/README.txt b/Master/texmf-dist/doc/latex/ptolemaicastronomy/README.txt
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+ptolemaicastronomy
+==================
+
+Diagrams of sphere models for variably strict conditionals (Lewis
+counterfactuals)
+
+Author: Richard Zach
+E-mail: rzach@ucalgary.ca
+License: Released under the LaTeX Project Public License v1.3c or later
+See: http://www.latex-project.org/lppl.txt
+
+David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+semantics for counterfactual conditionals. He jokingly referred to the
+diagrams depicting such sphere models as Ptolemaic astronomy, hence
+the name of this package. It has nothing to do with Ptolemy or with
+astronomy, sorry.
+
+The macros provided in this package aid in the construction of
+sphere model diagrams in the style of Lewis. The macros all make use
+of TikZ.
+
+See https://github.com/rzach/ptolemaic-astronomy
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/Master/texmf-dist/doc/latex/ptolemaicastronomy/ptolemaicastronomy.pdf b/Master/texmf-dist/doc/latex/ptolemaicastronomy/ptolemaicastronomy.pdf
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index 00000000000..82cbc042788
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/ptolemaicastronomy/ptolemaicastronomy.pdf
diff --git a/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.dtx b/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.dtx
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--- /dev/null
+++ b/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.dtx
@@ -0,0 +1,471 @@
+% \iffalse meta-comment
+% vim: textwidth=75
+%<*internal>
+\iffalse
+%</internal>
+%<*readme>
+ptolemaicastronomy
+==================
+
+Diagrams of sphere models for variably strict conditionals (Lewis
+counterfactuals)
+
+Author: Richard Zach  
+E-mail: rzach@ucalgary.ca  
+License: Released under the LaTeX Project Public License v1.3c or later  
+See: http://www.latex-project.org/lppl.txt
+
+David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+semantics for counterfactual conditionals. He jokingly referred to the
+diagrams depicting such sphere models as Ptolemaic astronomy, hence
+the name of this package. It has nothing to do with Ptolemy or with
+astronomy, sorry.
+
+The macros provided in this package aid in the construction of
+sphere model diagrams in the style of Lewis. The macros all make use
+of TikZ.
+
+See https://github.com/rzach/ptolemaic-astronomy
+
+%</readme>
+%<*internal>
+\fi
+\def\nameofplainTeX{plain}
+\ifx\fmtname\nameofplainTeX\else
+  \expandafter\begingroup
+\fi
+%</internal>
+%<*install>
+\input docstrip.tex
+\keepsilent
+\askforoverwritefalse
+\preamble
+
+ptolemaicastronomy
+==================
+
+Diagrams of sphere models for variably strict conditionals (Lewis
+counterfactuals)
+
+Author: Richard Zach
+E-mail: rzach@ucalgary.ca
+License: Released under the LaTeX Project Public License v1.3c or later
+See: http://www.latex-project.org/lppl.txt
+
+David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+semantics for counterfactual conditionals. He jokingly referred to the
+diagrams depicting such sphere models as Ptolemaic astronomy, hence
+the name of this package. It has nothing to do with Ptolemy or with
+astronomy, sorry.
+
+The macros provided in this package aid in the construction of
+sphere model diagrams in the style of Lewis. The macros all make use
+of TikZ.
+
+for documentation and source code see
+https://github.com/rzach/ptolemaic-astronomy
+
+\endpreamble
+\usedir{tex/latex/ptolemaicastronomy}
+\generate{
+  \file{\jobname.sty}{\from{\jobname.dtx}{package}}
+}
+%</install>
+%<install>\endbatchfile
+%<*internal>
+\usedir{source/latex/ptolemaicastronomy}
+\generate{
+  \file{\jobname.ins}{\from{\jobname.dtx}{install}}
+}
+\nopreamble\nopostamble
+\usedir{doc/latex/ptolemaicastronomy}
+\generate{
+  \file{README.txt}{\from{\jobname.dtx}{readme}}
+}
+\ifx\fmtname\nameofplainTeX
+  \expandafter\endbatchfile
+\else
+  \expandafter\endgroup
+\fi
+%</internal>
+% \fi
+%
+% \iffalse
+%<*driver>
+\ProvidesFile{ptolemaicastronomy.dtx}
+%</driver>
+%<package>\NeedsTeXFormat{LaTeX2e}[1999/12/01]
+%<package>\ProvidesPackage{ptolemaicastronomy}
+%<*package>
+    [2018/04/08 v1.00 Diagrams of sphere models for variably strict conditionals (Lewis counterfactuals)]
+%</package>
+%<*driver>
+\documentclass{ltxdoc}
+\usepackage[numbered]{hypdoc}
+\usepackage{\jobname}
+\usepackage{lstdoc}
+\EnableCrossrefs
+\CodelineIndex
+\RecordChanges
+\begin{document}
+  \DocInput{\jobname.dtx}
+\end{document}
+%</driver>
+% \fi
+%
+% \GetFileInfo{\jobname.dtx}
+% \DoNotIndex{\newcommand,\newenvironment}
+%
+%\title{\textsf{ptolemaicastronomy} --- Diagrams of sphere models for variably strict conditionals (Lewis counterfactuals)\thanks{This file
+%   describes version \fileversion, last revised \filedate.}
+%}
+%\author{Richard Zach\thanks{\href{http://richardzach.org/}{richardzach.org}, E-mail: rzach@ucalgary.ca}}
+%\date{Released \filedate}
+%
+%\maketitle
+%
+%\changes{v1.00}{2018/04/08}{First public release}
+%
+% \section{Introduction}
+
+% Lewis\footnote{David K. Lewis, \emph{Counterfactuals} (Blackwell
+% 1973)} introduced a sphere semantics for counterfactual
+% conditionals. He jokingly referred to the diagrams depicting such
+% sphere models as ``Ptolemaic astronomy,'' hence the name of this
+% package. It has nothing to do with Ptolemy or with astronomy, sorry.
+
+% The macros provided in this package aid in the construction of
+% sphere model diagrams in the style of Lewis. The macros all make use
+% of \href{https://ctan.org/tex-archive/graphics/pgf/}{Ti\emph{k}Z}.
+
+% Source code can be found at \url{https://github.com/rzach/ptolemaic-astronomy}
+%
+% \section{Usage}
+%
+% \DescribeMacro{\spheresystem}
+% To draw a sphere system with \meta{n} layers, say
+% \cmd{\spheresystem}\marg{n}:
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \spheresystem{5}
+%    \end{tikzpicture}
+% \end{lstsample}
+% The width of each layer is determined by the TikZ parameter
+% \verb|layerwidth| and defaults to $.5$ TikZ units (so $0.5$ cm by
+% default). The radius of the center sphere is \emph{not}
+% \verb|layerwidth|, but $\verb|layerwidth| \times (1 -
+% \verb|innerfactor|)$. \verb|innerfactor| defaults to $0.4$.
+% Spheres are drawn in \verb|dotted| style by default. You can change
+% this by passing an option to \cmd{\spheresystem}, e.g.,
+% to get red, dashed, thick lines and wider layers:
+% \begin{lstsample}{}{}
+%     \begin{tikzpicture}
+%       \spheresystem[dashed, red,
+%          thick, layerwidth=.75]{3}
+%     \end{tikzpicture}
+% \end{lstsample}
+% \DescribeMacro{\spherelayer} \DescribeMacro{\spherefill} These
+% macros shade the \meta{n}-th layer of the sphere model, or the
+% entire \meta{n}-th sphere. The fill defaults to \verb|lightgray| and
+% can be changed with \oarg{options}. Note that the fill extends to the
+% center of the layer boundary line, so you should fill first and then
+% draw the spheres. For instance:
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \spherelayer{3}
+%      \spherefill[yellow]{1}
+%      \spheresystem[densely dashed]{3}
+%    \end{tikzpicture}
+% \end{lstsample}
+% \DescribeMacro{\proposition}
+% \DescribeMacro{\propositionintersect}
+
+% A proposition is a set of worlds which (usually) intersects with a
+% sphere system. A common way of drawing them is as a parabola, and
+% often we want to highlight the intersection of the proposition with
+% the closest sphere with which it intersects.
+% \cmd{\proposition}\marg{direction}\marg{n}\marg{width}\marg{length}
+% will draw such a parabola. \meta{direction} is the angle (0 is due
+% east and 90 is due north) from which you want the proposition to
+% reach into the sphere system. \meta{n} is the innermost layer you
+% want it to intersect. \meta{width} and \meta{length} describe the
+% triangle with apex \meta{width} degrees and sides of length
+% \meta{length}. Use \cmd{\propositionintersect} to also highlight the
+% intersection with the \meta{n}-th sphere. E.g., here are
+% propositions that intersects the 3rd layer at 45 degrees, with a
+% width of 20, 40, and 60 degrees, and the intersection of the first
+% one with the innermost sphere it intersects.
+
+% With the \verb|shift| option you can also position propositions outside the center, e.g., a proposition extending from the north through the west side of the sphere system would use, say, \verb|shift={(-1,-1)}|.
+
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \propositionintersect{45}{3}{20}{3}
+%      \proposition{45}{3}{40}{3}
+%      \proposition{45}{3}{60}{3}
+%      \proposition[shift={(-1,-1)}]{90}{1}{20}{4}
+%      \spheresystem{5}
+%    \end{tikzpicture}
+% \end{lstsample}
+
+% The degree of ``pointedness'' of propositions is determined by the
+% \verb|tension| parameter, which defaults to $1.7$. Larger values
+% make the proposition more bulgy, smaller values more pointy.
+
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \proposition[green,
+%         proposition/.style={tension=3}]{0}{3}{80}{3}
+%      \proposition{0}{3}{80}{3}
+%      \proposition[red,
+%         proposition/.style={tension=1}]{0}{3}{80}{3}
+%      \proposition[blue,
+%         proposition/.style={tension=.5}]{0}{3}{80}{3}
+%      \spheresystem{5}
+%    \end{tikzpicture}
+% \end{lstsample}
+
+% \DescribeMacro{\spherepos}
+% \cmd{\spherepos}\marg{direction}\marg{n}\marg{code} moves to a
+% position in the center of layer \meta{n} in \meta{direction} and
+% then executes TikZ \verb|path| code \meta{code}. It's useful to put
+% labels or other things into the sphere system.
+
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \propositionintersect{45}{3}{20}{3}
+%      \spheresystem{5}
+%      \spherepos[fill,red]{45}{3}{circle[radius=.1]}
+%      \spherepos{90}{4}{node {$w$}}
+%      \spherepos{45}{6.5}{node {$\varphi$}}
+%    \end{tikzpicture}
+% \end{lstsample}
+
+% \DescribeMacro{\sphereintersect} \cmd{\propositionintersect} uses
+% \cmd{\sphereintersect}\oarg{options}\marg{n}\marg{code} to fill the
+% area between the parabola and the outside edge of the \meta{n}-th
+% sphere. (More precisely: what happens is that the area between the
+% parabola and the line between its two endpoints is set as the
+% clipping path, and then TikZ only shows the part of the shaded
+% sphere within that clipping path.) That macro can also be used to
+% intersect the respective layer with other paths, and in cases where
+% the convex closure of the proposition does not include enough area.
+% In that case, the clipping region has to be extended, and the path
+% drawn separately. The example below shows what happens when a very
+% wide parabola does not completely intersect with a sphere (on the
+% right), how to use the trick to get the fill right (on the left), as
+% well as how to intersect a more complex path with a sphere.
+
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}
+%      \propositionintersect{0}{3}{140}{3}
+%      \sphereintersect{3}{\propositionplot{180}{3}{140}{3} -- (-2,-2)}
+%      \proposition{180}{3}{140}{3}
+%      \sphereintersect{4}{plot[smooth] coordinates
+%          {(1.5,2) (2.5,1) (1.5,0) (2.5,-1) (1.5,-2) (2.5,-3)}}
+%      \draw[red] plot[smooth] coordinates
+%          {(1.5,2) (2.5,1) (1.5,0) (2.5,-1) (1.5,-2) (2.5,-3)} ;
+%      \spheresystem{5}
+%    \end{tikzpicture}
+% \end{lstsample}
+
+% Finally, a complex example: the Sobel sequence diagram, Figure~2 from Lewis, p.~11:
+% \begin{lstsample}{}{}
+%    \begin{tikzpicture}[scale=.8]\small
+%      % wider layers, pointier propositions
+%      \tikzset{layerwidth=1,innerfactor=0,
+%               proposition/.style={smooth,tension=1}}
+%      % fill the areas between three props and their innermost spheres
+%      \sphereintersect{3}{\propositionplot{30}{3.3}{30}{4}}
+%      \sphereintersect{2}{\propositionplot{30}{2.3}{45}{4}}
+%      \sphereintersect{1}{\propositionplot{30}{1.3}{60}{4}}
+%      % draw the sphere system
+%      \spheresystem{3}
+%      % draw the propositions
+%      \draw \propositionplot{30}{3.3}{30}{4};
+%      \draw \propositionplot{30}{2.3}{45}{4};
+%      \draw \propositionplot{30}{1.3}{60}{4};
+%      % draw \psi (coordinates figured out by trial and error)
+%      \draw plot[smooth,tension=1.2]
+%        coordinates {(-1.5,3) (1.2,-1) (.8,2.3) (2.8,.7) (3,4)};
+%      % draw and label the center world, spheres, and propositions
+%      \filldraw circle[radius=.05];
+%      \node at (-.2,-.2) {$i$};
+%      \spherepos{-70}{1.8}{node {$S^1_i$}}
+%      \spherepos{-70}{2.8}{node {$S^2_i$}}
+%      \spherepos{-70}{3.8}{node {$S^3_i$}}
+%      \spherepos{4}{4.3}{node {$\phi_1$}
+%                         node at +(0,.5) {$\phi_2$}
+%                         node at +(0,1) {$\phi_3$}}
+%      \spherepos{80}{4}{node {$\psi$}}
+%    \end{tikzpicture}
+% \end{lstsample}
+
+%\StopEventually{^^A
+%  \PrintChanges
+%  \PrintIndex
+%}
+%
+% \section{Implementation}
+%
+% \iffalse
+%<*package>
+% \fi
+%
+%    \begin{macrocode}
+\RequirePackage{tikz}
+
+\tikzset{
+  sphere/.style = {dotted},
+  sphere intersection/.style = {fill=lightgray},
+  sphere layer/.style = {fill=lightgray},
+  proposition/.style={smooth,tension=1.7},
+}
+%    \end{macrocode}
+% \begin{macro}{layerwidth}
+% \begin{macro}{innerfactor}
+% TikZ parameters used to compute the sphere radii and can be set
+% using TikZ's options mechanism or using \cmd{\tikzset}.
+%    \begin{macrocode}
+\pgfkeyssetvalue{/tikz/layerwidth}{.5}
+\pgfkeyssetvalue{/tikz/innerfactor}{.4}
+%    \end{macrocode}
+% \end{macro}\end{macro}
+% \begin{macro}{\sphereplot}
+% \cmd{\sphereplot}\marg{n} gives the plot codes for the \meta{n}-th sphere
+%    \begin{macrocode}
+\newcommand{\sphereplot}[1]{
+  circle
+    [radius=(#1)*\pgfkeysvalueof{/tikz/layerwidth}-
+      \pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor}]
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%
+% \begin{macro}{\spheresystem}
+% \cmd{\spheresystem}\oarg{options}\marg{n} draws a sphere system centered at
+% the origin with \meta{n} number of layers
+%
+%    \begin{macrocode}
+\newcommand{\spheresystem}[2][]{
+  \foreach \i in {1,...,#2}{
+    \draw[sphere,#1] \sphereplot{\i} ;
+  }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+
+%
+%
+% \begin{macro}{\spherelayer}
+% \cmd{\spherelayer}\oarg{options}\marg{n} shades the \meta{n}-th layer
+%    \begin{macrocode}
+\newcommand{\spherelayer}[2][]{
+  \begin{scope}[even odd rule]
+    \fill[#1,sphere layer]
+    \sphereplot{#2-1} \sphereplot{#2} ;
+  \end{scope}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\spherefill}
+%
+% \cmd{\spherefill}\oarg{options}\marg{n} fills the \meta{n}-th sphere
+%
+%    \begin{macrocode}
+\newcommand{\spherefill}[2][]{
+    \fill[sphere intersection,#1]
+    \sphereplot{#2} ;
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%
+% \begin{macro}{\sphereintersect}
+% \cmd{\sphereintersect}\oarg{options}\marg{n}\marg{path} shades the
+% area between \meta{path} and the the \meta{n}-th sphere
+% layer. Options only apply to the sphere layer.
+% \begin{macrocode}
+\newcommand{\sphereintersect}[3][]{
+  \begin{scope}[even odd rule]
+    \path[clip] #3;
+    \spherefill[#1]{#2}
+  \end{scope}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%
+%
+% \begin{macro}{\propositionplot}
+% \cmd{\propositionplot}\oarg{options}\marg{direction}\marg{n}\marg{width}\marg{length}
+% produces the \verb|plot| code for a proposition intersecting the \meta{n}-th layer in angle \meta{direction}
+% away from the center of the sphere system, with endpoints \meta{length}
+% away from the center at an angle of $\meta{direction} \pm \meta{width}/2$.
+%    \begin{macrocode}
+\newcommand{\propositionplot}[4]{
+  plot [proposition]
+  coordinates {+(#1+#3/2:#4)
+    +(#1:#2*\pgfkeysvalueof{/tikz/layerwidth}-
+    \pgfkeysvalueof{/tikz/layerwidth}*.9
+    -\pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor})
+    +(#1-#3/2:#4)}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%
+% \begin{macro}{\proposition}
+% \cmd{\proposition}\oarg{options}\marg{direction}\marg{n}\marg{width}\marg{length}
+% actually draws the proposition. Note that \meta{options} applies to
+% \cmd{\draw}, not to \cs{plot}. 
+%    \begin{macrocode}
+\newcommand{\proposition}[5][]{
+  \draw[proposition,#1] \propositionplot {#2}{#3}{#4}{#5} ;
+  }
+%    \end{macrocode}
+% \end{macro}
+%
+%
+% \begin{macro}{\propositionintersect}
+% \cmd{\spherepropositionintersect} does the same as \cmd{\sphereproposition} but
+% also shades the area of intersection with the \meta{n}-th sphere.
+%
+%    \begin{macrocode}
+\newcommand{\propositionintersect}[5][]{
+  \begin{scope}
+  \path[clip] \propositionplot{#2}{#3}{#4}{#5};
+  \spherefill[#1]{#3}
+  \end{scope}
+  \draw[proposition,#1] \propositionplot{#2}{#3}{#4}{#5};
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\spherepos}
+% \cmd{\spherepos}\oarg{options}\marg{direction}\marg{n}\marg{code}
+% shifts the scope to a position in the center of the \meta{n}-th layer in
+% direction angle from the center---and then puts a \meta{code} \verb|path|
+% there.
+%\begin{macrocode}
+\newcommand{\spherepos}[4][]{
+  \begin{scope}[shift=(#2:#3*\pgfkeysvalueof{/tikz/layerwidth}-
+      \pgfkeysvalueof{/tikz/layerwidth}/2-
+        \pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor})]
+    \path[#1] #4 ;
+  \end{scope}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%
+% \iffalse
+%</package>
+% \fi
+%
+% \Finale
+\endinput
+
diff --git a/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.ins b/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.ins
new file mode 100644
index 00000000000..cb405082036
--- /dev/null
+++ b/Master/texmf-dist/source/latex/ptolemaicastronomy/ptolemaicastronomy.ins
@@ -0,0 +1,84 @@
+%%
+%% This is file `ptolemaicastronomy.ins',
+%% generated with the docstrip utility.
+%%
+%% The original source files were:
+%%
+%% ptolemaicastronomy.dtx  (with options: `install')
+%% 
+%% ptolemaicastronomy
+%% ==================
+%% 
+%% Diagrams of sphere models for variably strict conditionals (Lewis
+%% counterfactuals)
+%% 
+%% Author: Richard Zach
+%% E-mail: rzach@ucalgary.ca
+%% License: Released under the LaTeX Project Public License v1.3c or later
+%% See: http://www.latex-project.org/lppl.txt
+%% 
+%% David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+%% semantics for counterfactual conditionals. He jokingly referred to the
+%% diagrams depicting such sphere models as Ptolemaic astronomy, hence
+%% the name of this package. It has nothing to do with Ptolemy or with
+%% astronomy, sorry.
+%% 
+%% The macros provided in this package aid in the construction of
+%% sphere model diagrams in the style of Lewis. The macros all make use
+%% of TikZ.
+%% 
+%% for documentation and source code see
+%% https://github.com/rzach/ptolemaic-astronomy
+%% 
+\input docstrip.tex
+\keepsilent
+\askforoverwritefalse
+\preamble
+
+ptolemaicastronomy
+==================
+
+Diagrams of sphere models for variably strict conditionals (Lewis
+counterfactuals)
+
+Author: Richard Zach
+E-mail: rzach@ucalgary.ca
+License: Released under the LaTeX Project Public License v1.3c or later
+See: http://www.latex-project.org/lppl.txt
+
+David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+semantics for counterfactual conditionals. He jokingly referred to the
+diagrams depicting such sphere models as Ptolemaic astronomy, hence
+the name of this package. It has nothing to do with Ptolemy or with
+astronomy, sorry.
+
+The macros provided in this package aid in the construction of
+sphere model diagrams in the style of Lewis. The macros all make use
+of TikZ.
+
+for documentation and source code see
+https://github.com/rzach/ptolemaic-astronomy
+
+\endpreamble
+\usedir{tex/latex/ptolemaicastronomy}
+\generate{
+  \file{\jobname.sty}{\from{\jobname.dtx}{package}}
+}
+\endbatchfile
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+\endinput
+%%
+%% End of file `ptolemaicastronomy.ins'.
diff --git a/Master/texmf-dist/tex/latex/ptolemaicastronomy/ptolemaicastronomy.sty b/Master/texmf-dist/tex/latex/ptolemaicastronomy/ptolemaicastronomy.sty
new file mode 100644
index 00000000000..6d132d47091
--- /dev/null
+++ b/Master/texmf-dist/tex/latex/ptolemaicastronomy/ptolemaicastronomy.sty
@@ -0,0 +1,114 @@
+%%
+%% This is file `ptolemaicastronomy.sty',
+%% generated with the docstrip utility.
+%%
+%% The original source files were:
+%%
+%% ptolemaicastronomy.dtx  (with options: `package')
+%% 
+%% ptolemaicastronomy
+%% ==================
+%% 
+%% Diagrams of sphere models for variably strict conditionals (Lewis
+%% counterfactuals)
+%% 
+%% Author: Richard Zach
+%% E-mail: rzach@ucalgary.ca
+%% License: Released under the LaTeX Project Public License v1.3c or later
+%% See: http://www.latex-project.org/lppl.txt
+%% 
+%% David K. Lewis (Counterfactuals, Blackwell 1973) introduced a sphere
+%% semantics for counterfactual conditionals. He jokingly referred to the
+%% diagrams depicting such sphere models as Ptolemaic astronomy, hence
+%% the name of this package. It has nothing to do with Ptolemy or with
+%% astronomy, sorry.
+%% 
+%% The macros provided in this package aid in the construction of
+%% sphere model diagrams in the style of Lewis. The macros all make use
+%% of TikZ.
+%% 
+%% for documentation and source code see
+%% https://github.com/rzach/ptolemaic-astronomy
+%% 
+\NeedsTeXFormat{LaTeX2e}[1999/12/01]
+\ProvidesPackage{ptolemaicastronomy}
+    [2018/04/08 v1.00 Diagrams of sphere models for variably strict conditionals (Lewis counterfactuals)]
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+\RequirePackage{tikz}
+
+\tikzset{
+  sphere/.style = {dotted},
+  sphere intersection/.style = {fill=lightgray},
+  sphere layer/.style = {fill=lightgray},
+  proposition/.style={smooth,tension=1.7},
+}
+\pgfkeyssetvalue{/tikz/layerwidth}{.5}
+\pgfkeyssetvalue{/tikz/innerfactor}{.4}
+\newcommand{\sphereplot}[1]{
+  circle
+    [radius=(#1)*\pgfkeysvalueof{/tikz/layerwidth}-
+      \pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor}]
+}
+\newcommand{\spheresystem}[2][]{
+  \foreach \i in {1,...,#2}{
+    \draw[sphere,#1] \sphereplot{\i} ;
+  }
+}
+
+\newcommand{\spherelayer}[2][]{
+  \begin{scope}[even odd rule]
+    \fill[#1,sphere layer]
+    \sphereplot{#2-1} \sphereplot{#2} ;
+  \end{scope}
+}
+\newcommand{\spherefill}[2][]{
+    \fill[sphere intersection,#1]
+    \sphereplot{#2} ;
+}
+\newcommand{\sphereintersect}[3][]{
+  \begin{scope}[even odd rule]
+    \path[clip] #3;
+    \spherefill[#1]{#2}
+  \end{scope}
+}
+\newcommand{\propositionplot}[4]{
+  plot [proposition]
+  coordinates {+(#1+#3/2:#4)
+    +(#1:#2*\pgfkeysvalueof{/tikz/layerwidth}-
+    \pgfkeysvalueof{/tikz/layerwidth}*.9
+    -\pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor})
+    +(#1-#3/2:#4)}
+}
+\newcommand{\proposition}[5][]{
+  \draw[proposition,#1] \propositionplot {#2}{#3}{#4}{#5} ;
+  }
+\newcommand{\propositionintersect}[5][]{
+  \begin{scope}
+  \path[clip] \propositionplot{#2}{#3}{#4}{#5};
+  \spherefill[#1]{#3}
+  \end{scope}
+  \draw[proposition,#1] \propositionplot{#2}{#3}{#4}{#5};
+}
+\newcommand{\spherepos}[4][]{
+  \begin{scope}[shift=(#2:#3*\pgfkeysvalueof{/tikz/layerwidth}-
+      \pgfkeysvalueof{/tikz/layerwidth}/2-
+        \pgfkeysvalueof{/tikz/layerwidth}*\pgfkeysvalueof{/tikz/innerfactor})]
+    \path[#1] #4 ;
+  \end{scope}
+}
+\endinput
+%%
+%% End of file `ptolemaicastronomy.sty'.
diff --git a/Master/tlpkg/bin/tlpkg-ctan-check b/Master/tlpkg/bin/tlpkg-ctan-check
index 2d29b8acd21..3a80214bd72 100755
--- a/Master/tlpkg/bin/tlpkg-ctan-check
+++ b/Master/tlpkg/bin/tlpkg-ctan-check
@@ -563,7 +563,7 @@ my @TLP_working = qw(
     pst-vectorian pst-vehicle pst-venn pst-vowel pst-vue3d
     pst2pdf pstool pstricks pstricks-add pstricks_calcnotes pstring
     ptex-base ptex-fontmaps ptex-fonts ptex-manual
-    ptex2pdf ptext ptptex
+    ptex2pdf ptext ptolemaicastronomy ptptex
     punk punk-latex punknova purifyeps pxbase
     pxchfon pxcjkcat pxfonts pxgreeks pxjahyper pxjodel
     pxpgfmark pxrubrica pxtatescale pxtxalfa pxufont
diff --git a/Master/tlpkg/tlpsrc/collection-pictures.tlpsrc b/Master/tlpkg/tlpsrc/collection-pictures.tlpsrc
index 22156a79679..9e94aac4525 100644
--- a/Master/tlpkg/tlpsrc/collection-pictures.tlpsrc
+++ b/Master/tlpkg/tlpsrc/collection-pictures.tlpsrc
@@ -113,6 +113,7 @@ depend pmgraph
 depend postage
 depend prerex
 depend productbox
+depend ptolemaicastronomy
 depend pxpgfmark
 depend qcircuit
 depend quantikz
diff --git a/Master/tlpkg/tlpsrc/ptolemaicastronomy.tlpsrc b/Master/tlpkg/tlpsrc/ptolemaicastronomy.tlpsrc
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/Master/tlpkg/tlpsrc/ptolemaicastronomy.tlpsrc