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README.md

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+# Truth Table
+This is a simple truth table generator. For more information about truth tables,
+please see the [relevant Wikipedia article][1].
+
+[1]: https://en.wikipedia.org/wiki/Truth_table 
+
+To build, just run `make`. You will need SBCL, as well as Quicklisp. Quicklisp
+is used to load `uiop` and `with-user-abort`.
+
+The format of the input propositions is fairly free-form. The above Wikipedia
+article has some information about their format, as well as possible symbols for
+operators. You can also take a look at the table near the top of
+`truth-table.lisp` for all the variations supported by this program.
+
+Here is the help output from the program:
+```text
+usage: truth-table [options] <propositions...>
+
+  -h, --help          print this message, then exit
+  -f, --format=<arg>  specify the output format (*unicode*, ascii, or latex)
+  -s, --subexps       include sub-expressions in the output table
+  -n, --no-vars       do not include variables in the output table
+  -m, --multi-char    allow multi-character variable names
+  -i, --no-implicit   do not use implicit 'and' operations
+
+The choice surrounded by '*' is the default. Arguments to long
+options are also required for their short variant.
+```
+
+Here is an example truth table:
+```text
+$ truth-table '(a /\ b) -> ~b'
+
+┌───┬───┬────────────┐
+│ a │ b │ a ∧ b → ¬b │
+├───┼───┼────────────┤
+│ ⊤ │ ⊤ │     ⊥      │
+│ ⊤ │ ⊥ │     ⊤      │
+│ ⊥ │ ⊤ │     ⊤      │
+│ ⊥ │ ⊥ │     ⊤      │
+└───┴───┴────────────┘
+```