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THE COMMON BUSINESS
Computer Science Department
Stanford, CA 94305
1999 May 7, 1:55 p.m.
This paper, written in 1975, published in 1982 [McC82] in the
proceedings of a conference whose title was in German, seems to be
worth reviving in 1998, because some of its ideas are new in 1998 (I’m
told) and are relevant to the new interest in electronic commerce.
1 The Problem of Inter-computer Communi-
Here are some ideas about the value of a common business communication
language (CBCL for short) and what its characteristics might be. Besides its
practical signiﬁcance, CBCL raises issues concerning the semantics of natural
The need for such a language was suggested to me by an article by Paul
Baran [Bar67].1 In this article, Baran envisaged a world of the future in which
11998 footnote: The question became salient for me when I attended a DARPA meeting
in 1969 at which the Navy’s Fleet Data System was described.
companies would be well equipped with on-line computer systems. The in-
ventory control computer of company A would write on the screen of a clerk
in the purchasing department a statement that 1000 gross of such-and-such
pencils were needed and that they should be purchased from company B.
The clerk would turn to her typewriter and type out a purchase order. At
company B another clerk would receive the purchase order and turn to her
terminal and tell the computer to arrange to ship the pencils. Eliminat-
ing both clerks by having the computers speak directly to each other was
not mentioned. Perhaps the author felt that he was already straining the
credulity of his audience.
Suppose we wish to eliminate the clerks by having the computers speak
directly to each other. What are the requirements?
First, computers do communicate directly now (1975). In the late 1950s the
Social Security Administration announced a format for IBM seven channel
magnetic tape on which it was prepared to receive reports of earnings and
payroll deductions. Note the limitations: (i) magnetic tapes are mailed rather
than direct electronic communication—admittedly entirely appropriate in
this case. (ii) A single ﬁxed kind of message with a ﬁxed set of parameters
exists for each report. (iii) There is only one receiver of information which
can dictate the format. Today information is often exchanged electronically
among computer systems belonging to diﬀerent organizations, and this is
usually by speciﬁc treaty betwen the two organizations, but sometimes a
group that will be communicating has agreed on formats. An example is
the U.S. Navy’s Fleet Data System for exchanging information among ships
about what their radars and other sensors can see so that each ship can have
the full radar picture acquired by the whole ﬂeet. In connection with the
extension of the system to NATO, it was completely redesigned, and on a
designated day, all users switched to the new system.
Our goal is more ambitious in the following respects:
sell, queries about delivery times and places, inquiries about the status of de-
layed orders, references to standard commercial legal agreements. If possible,
the same language should with only diﬀerent primitives suﬃce to communi-
cate the Navy’s or the FAA’s radar information or a request from one state’s
department of motor vehicles to another’s for a list of a person’s traﬃc con-
this requires authentication procedures and veriﬁcation of authorization pro-
cedures, but let us not be unduly distracted by the security aspects of com-
puting lest we end up with a secure method of communication and nothing
to inquire about speciﬁcations and prices and decide on the best deal. This
requires that each message be translatable into a human-comprehensible form
and that each computer have a way of referring messages it is not yet pro-
grammed to understand to humans. When a new type of message is to
displace an old one, the programs should send both until all the receivers
can understand the new form. Thus the crises of cutover days, as in the
naval example, could be eliminated.3
municated, and it should not presuppose anything about the programs that
use the language. Each business using the language would have a program
designed to use the particular part of CBCL relevant to its business commu-
nications. Thus CBCL presupposes nothing about the programs that decide
when to order or what orders to accept.
to remark that the system should avoid traps in these areas, and the users
should be able to change their systems asynchronously. Presumably CBCL
would use the same low level protocols used for more simple inter-business
communications like person-to-person messages and ﬁle transfer.
We do not have a ﬁnal proposal but here are some ideas:
to interpret the rest. The items may be either sublists or atoms. If an item
21998 footnote: Emphasizing security over content is still a problem.
31998 footnote: I didn’t see this in the ICE literature.
is a sublist, its ﬁrst element tells how to interpret it. Atoms are binary
numbers of say 32 bits. A dictionary tells what each means. Other forms of
data may be used provided they are demarcated by appropriate punctuation
and provided they are pointed at from lists that tell how they are to be
[1998: The above two examples correspond directly to what has been
proposed for ICE apart from the names of the structures.]
c. (REQUEST-QUOTE (ADJECTIVE (PENCILS #2) YELLOW) (GROSS100))
[1998: The point of ADJECTIVE is that a program not understanding
YELLOW could nevertheless understand that #2 pencils were called for, and
could reply that they don’t have any pencils, if that were so.]
d. (WE-QUOTE (OUR-STOCK-NUMBER A7305) (QUANTITY 100)
(DELIVERY-DATE 3-10-77) (PRICE $1.00))
[1998: This is also standard today.]
41998 footnote: This list format is isomorphic to XML but simpler. The ﬁrst example
<YOUR-STOCK-NUMBER> A7305 </YOUR-STOCK-NUMBER>
<UNITS> 100 </UNITS>
below translated into XML becomes
with no obvious beneﬁt over
e. (PLEASE-SAY (IOTA (X) (AND (RED X) (PENCIL X))))
[1998: This uses the Russell description operator, essentially correspond-
ing to the English word “the”. [1998: That’s not such a good example. Here’s
a better one using the Hilbert (cid:15) (epsilon) symbol: (PLEASE-RESERVE (EP-
SILON (X) (AND (IS-FLIGHT X) (DEPARTS MONDAY) (ARRIVES (BE-
FORE WEDNESDAY))))). ((cid:15)x)P (x) stands for “an x such that P (x). If you
don’t like (cid:15), you can write (AN (X). . . ,etc. This raises a general expression
about variable binders. CBCL proposes to handle them in a standard way,
namely (<binder> (<variables> <body>), i.e. all binders including those
to be invented in the future are handled the same. The logical operators
AND, OR, and NOT are also to be standard where used at all.]
It appears that some items may require a variable number of modiﬁers.
As a toy example, imagine writing conventions that would permit any
Monopoly-like game to be played by independently written programs. Sup-
pose that the moves are communicated to a referee who receives requests to
roll the dice and returns information about what squares the pieces landed
on and what ‘chance’ cards were drawn. The programs would communicate
oﬀers to buy and sell directly to each other and to the ‘banker’.
CBCL should have an important property enunciated by Chomsky in his
Reﬂections on Language as a characteristic of human language. (Linguists
tell me that whether natural languages have it is controversial; but whether
they do or don’t, CBCL shall have it.) The principle (reworded considerably)
is that no grammatical position should require an identiﬁer or a number
per se but should allow a phrase. For example, instead of requiring a stock
number, an expression designating the stock number, such as ‘the same stock
number as last week’ or ‘the new stock number of the item that was formerly
stock number 2531’. We don’t really mean these English phrases but rather
whatever CBCL expression translates into them. 5
3 CBCL and natural language
Developing an expressive CBCL has proved unexpectedly diﬃcult. Even
concentrating on the idea of a purchase order doesn’t easily lead to deﬁning
formats that permit expressing all that should be possible to include in a
purchase order. The problem is that every aspect of the purchase order
5This isn’t part of the ICE speciﬁcation as far as I can see.
such as the delivery method or the terms of payment seems to admit inﬁnite
variation and elaboration. It is a semantic feature of natural language that
this elaboration is possible. The problems do not at all stem from the rigid
list syntax of CBCL, which after all resembles the result of parsing a natural
language text. The problems are in the semantics, i.e., in specifying what
should be expressible.
This suggests that the problem of formalizing what is expressible in nat-
ural language can and should be studied entirely separately from the syntax.
In addition it suggests that putting natural language front ends on com-
puter programs often entirely misses the key problems of natural language.
Namely, before the natural language front end is attached, the programmer
has already decided what things shall be sayable, and they are usually things
that can readily be said in a pre-existing input-output system. But if we are
right, the most diﬃcult problems in making a computer use language involve
deciding what is to be sayable.
For example, consider some possible speciﬁcations of the method of de-
Unfortunately, these few examples do not show the scope of the problem.
In order to make sense of expressions like those in the above examples
programs that use CBCL will have to be capable of non-monotonic reasoning.
Namely, they will need to be able to give the most standard interpretations of
the messages compatible with what has been said explicitly. Circumscription
has been proposed as a tool for this.
1998: Advice for XML, W3 and ICE
This summarizes and extends remarks made in the 1998 footnotes.
will be required.
ﬁrst item in a list is required to be atomic.
the rest of the list is to be interpreted. I don’t know whether this would
get much use in CBCL or XML.
stand YELLOW but which can understand FOO may be able to do
something useful with the information, given the convention that (AD-
JECTIVE x y) is a kind of y. Many English adjectives are not used
this way, and we propose only to use such proper adjectives.
systems don’t do this properly, e.g. with time strings, and I notice
that the W3 draft doesn’t either. In Lisp a time has the string format
exempliﬁed by Wed Nov 11 12:58:28 1998.
It should also allow the
format (TIME <weekday> <month> <hour> <minute> <second>).
The operators on such string should have the names they would have
in the list or XML format.
[Bar67] Paul Baran. The future computer utility. The Public Interest,
[McC82] John McCarthy. Common Business Communication Language6.
In Albert Endres and J¨urgen Reetz, editors, Textverarbeitung und
B¨urosysteme. R. Oldenbourg Verlag, Munich and Vienna, 1982.
/@steam.stanford.edu:/u/ftp/jmc/cbcl.tex: begun 1996 May 14, latexed 1999 May 7 at 1:55 p.m.