1 # Seminar in Semantics / Philosophy of Language #
3 or: **What Philosophers and Linguists Can Learn From Theoretical Computer Science But Didn't Know To Ask**
5 This course will be co-taught by [Chris Barker](http://homepages.nyu.edu/~cb125/) and [Jim Pryor](http://www.jimpryor.net/). Linguistics calls it "G61.3340-002" and Philosophy calls it "G83.2296-001."
10 The seminar meets on Mondays, starting September 13, from 4-6 in the 2nd floor Philosophy Seminar Room, at 5
11 Washington Place. We may be able to shift the time around slightly to suit the
12 schedule of participants; but it will remain on Mondays late
19 The goal of this seminar is to introduce concepts and techniques from
20 theoretical computer science and show how they can provide insight
21 into established philosophical and linguistic problems.
23 This is not a seminar about any particular technology or software.
24 Rather, it's about a variety of conceptual/logical ideas that have been
25 developed in computer science and that linguists and philosophers ought to
26 know, or may already be unknowingly trying to reinvent.
28 Philosphers and linguists tend to reuse the same familiar tools in
29 ever more (sometime spectacularly) creative ways. But when your only
30 hammer is classical logic, every problem looks like modus ponens. In
31 contrast, computer scientists have invested considerable ingenuity in
32 studying tool design, and have made remarkable progress.
34 "Why shouldn't I reinvent some idea X for myself? It's intellectually
35 rewarding!" Yes it is, but it also takes time you might have better
36 spent elsewhere. After all, you can get anywhere you want to go by walking, but you can
37 accomplish more with a combination of walking and strategic subway
40 More importantly, the idiosyncrasies of your particular
41 implementation may obscure what's fundamental to the idea you're
42 working with. Your implementation may be buggy in corner cases you
43 didn't think of; it may be incomplete and not trivial to generalize; its
44 connection to existing literature and neighboring issues may go
45 unnoticed. For all these reasons you're better off understanding the
48 The theoretical tools we'll be introducing aren't very familiar to
49 everyday programmers, but they are prominent in academic computer science,
50 especially in the fields of functional programming and type theory.
52 Of necessity, this course will lay a lot of logical groundwork. But throughout
53 we'll be aiming to mix that groundwork with real cases
54 in our home subjects where these tools play central roles. Our aim for the
55 course is to enable you to make these tools your own; to have enough
56 understanding of them to recognize them in use, use them yourself at least
57 in simple ways, and to be able to read more about them when appropriate.
59 Once we get up and running, the central focii of the course will be
60 **continuations**, **types**, and **monads**. One of the on-going themes will
61 concern evaluation order and issues about how computations (inferences,
62 derivations) unfold in (for instance) time. The key analytic technique is to
63 form a static, order-independent model of a dynamic process. We'll be
64 discussing this in much more detail as the course proceeds.
66 The logical systems we'll be looking at include:
68 * the pure/untyped lambda calculus
70 * the simply-typed lambda calculus
71 * polymorphic types with System F
72 * some discussion of dependent types
73 * if time permits, "indeterministic" or "preemptively parallel" computation and linear logic
78 recursion using the Y-combinator
79 evaluation-order stratgies
80 normalizing properties
81 the Curry-Howard isomorphism(s)
82 monads in category theory and computation
85 ## Who Can Participate? ##
87 The course will not presume previous experience with programming. We
88 will, however, discuss concepts embodied in specific programming
89 languages, and we will encourage experimentation with running,
90 modifying, and writing computer programs.
92 The course will not presume lots of mathematical or logical background, either.
93 However, it will demand a certain amount of comfort working with such material; as a result,
94 it will not be especially well-suited to be a first graduate-level course
95 in formal semantics or philosophy of language. If you have concerns about your
96 background, come discuss them with us.
98 This class will count as satisfying the logic requirement for Philosophy
99 PhD students; however if this would be your first or only serious
100 engagement with graduate-level formal work you should consider
101 carefully, and must discuss with us, (1) whether you'll be adequately
102 prepared for this course, and (2) whether you'd be better served by
103 taking a logic course (at a neighboring department, or at NYU next year)
104 with a more canonical syllabus.
107 Faculty and students from outside of NYU Linguistics and Philosophy are welcome
108 to audit, to the extent that this coheres well with the needs of our local
112 ## Recommended Software ##
114 During the course, we'll be encouraging you to try out various things in Scheme
115 and Caml, which are prominent *functional programming languages*. We'll explain
116 what that means during the course.
118 * **Scheme** is one of two major dialects of *Lisp*, which is a large family
119 of programming languages. The other dialect is called "CommonLisp." Scheme
120 is the more clean and minimalistic dialect, and is what's mostly used in
122 Scheme itself has umpteen different "implementations", which share most of
123 their fundamentals, but have slightly different extensions and interact with
124 the operating system differently. One major implementation used to be called
125 PLT Scheme, and has just in the past few weeks changed their name to Racket.
126 This is what we recommend you use. (If you're already using or comfortable with
127 another Scheme implementation, though, there's no compelling reason to switch.)
129 * **Caml** is one of two major dialects of *ML*, which is another large
130 family of programming languages. The other dialect is called "SML" and has
131 several implementations. But Caml has only one active implementation,
132 OCaml, developed by the INRIA academic group in France.
134 * Those of you with some programming background may have encountered a third
135 prominent functional programming language, **Haskell**. This is also used a
136 lot in the academic contexts we'll be working through. Its surface syntax
137 differs from Caml, and there are various important things one can do in
138 each of Haskell and Caml that one can't (or can't as easily) do in the
139 other. But these languages also have a lot in common, and if you're
140 familiar with one of them, it's not difficult to move between it and the
143 [[How to get the programming languages running on your computer]]
145 [[Using the programming languages]]
147 [[Family tree of functional programming languages]]
149 ## Recommended Books ##
151 * *An Introduction to Lambda Calculi for Computer Scientists*, by Chris
152 Hankin, currently $17 on
153 [Amazon](http://www.amazon.com/Introduction-Lambda-Calculi-Computer-Scientists/dp/0954300653).
155 * (Another good book covering the same ground as the Hankin book, but
156 more thoroughly, and in a more mathematical style, is *Lambda-Calculus and Combinators:
157 an Introduction*, by J. Roger Hindley and Jonathan P. Seldin. If you choose to read
158 both the Hankin book and this book, you'll notice the authors made some different
159 terminological/notational choices. At first, this makes comprehension slightly slower,
160 but in the long run it's helpful because it makes the arbitrariness of those choices more salient.)
163 * *The Little Schemer, Fourth Edition*, by Daniel P. Friedman and Matthias
164 Felleisen, currently $23 on [Amazon](http://www.amazon.com/exec/obidos/ASIN/0262560992).
165 This is a classic text introducing the gentle art of programming, using the
166 functional programming language Scheme. Many people love this book, but it has
167 an unusual dialog format that is not to everybody's taste. **Of particular
168 interest for this course** is the explanation of the Y combinator, available as
169 a free sample chapter [at the MIT Press web page for the
170 book](http://www.ccs.neu.edu/home/matthias/BTLS/).
172 * *The Seasoned Schemer*, also by Daniel P. Friedman and Matthias Felleisen, currently $28
173 on [Amazon](http://www.amazon.com/Seasoned-Schemer-Daniel-P-Friedman/dp/026256100X)
175 * *The Little MLer*, by Matthias Felleisen and Daniel P. Friedman, currently $27
176 on [Amazon](http://www.amazon.com/Little-MLer-Matthias-Felleisen/dp/026256114X).
177 This covers some of the same introductory ground as The Little Schemer, but
178 this time in ML. The dialect of ML used is SML, not OCaml, but there are only
179 superficial syntactic differences between these languages. [Here's a translation
180 manual between them](http://www.mpi-sws.org/~rossberg/sml-vs-ocaml.html).
182 ##[[Schedule of Topics]]##
184 ##[[Lecture Notes]]##
186 ##[[Offsite Reading]]##
188 There's lots of links here already to tutorials and encyclopedia entries about many of the notions we'll be dealing with.
193 All wikis are supposed to have a [[SandBox]], so this one does too.
195 This wiki is powered by [[ikiwiki]].