Information Technology Reference
In-Depth Information
Analogies
Analogies are curious things: what seems perfectly alike or parallel to one person
may seem entirely unalike to another.
Writing a program is like building a model with connector blocks.
What are “connector blocks”? How are they like programming? Even if the similarity
is obvious to a programmer, is it obvious to a novice? This analogy (made in an
introductory computer science textbook) seems to me to fail because it captures
neither logic nor repetition. For an analogy to be worthwhile, it should significantly
reduce the work of understanding the concept being described.
Another drawback to analogies is that they can take your reasoning astray—two
situations with marked similarities may nonetheless have fundamental differences
that the analogy leads you to ignore. I have seen more bad analogies than good in
computing research papers; however, simple analogies can undoubtedly help illus-
trate unfamiliar concepts.
Contrasting look-ahead graph traversal with standard approaches, look-ahead
uses a bird's-eye view of the local neighbourhood to avoid dead ends, but at
significant cost: it is necessary to feed the bird and wait for it to return after
each observation.
Beware of analogies with situations that may be unfamiliar to the reader.
One-sided protocols are like signals in football.
Straw Men
A straw man is an indefensible hypothesis that an author describes for the sole
purpose of criticizing it. A paraphrasing of an instance in a published paper is “it
can be argued that databases do not require indexes”, in which the author and reader
are well aware that a database without an index is as practical as a library without a
catalogue.
Such writing says more about the author than it does about the subject. For exam-
ple, occasionally an author will write something like:
As the scale of data on the Web grows to billions of pages, searchers can no
longer find answers to queries.
Sweeping statements of this kind, in this case thoroughly contradicted by our daily
experience of search, tell the reader that the work is not based on rigorous argument
or clear thinking.
Another form of straw man is the contrasting of a new idea with some impossibly
bad alternative, to put the new idea in a favourable light. This form is obnoxious
because it can lead the reader to believe that the impossibly bad idea might be
