From Simple English Wikipedia, the free encyclopedia
A
diagnosis
is an accurate and precise account of the nature or
cause
of something.
Medical diagnosis
is the best-known field, but diagnosis can be applied to any subject. Whereas a doctor diagnoses what is wrong with a patient, a motor mechanic can diagnose the
fault
in a car. In all cases they replace a vague query, such as "My car will not start", with an exact
analysis
, such as "It's out of petrol". Notice the diagnosis is precise enough so the solution can be seen.
These ideas work even in more subtle cases. A boy brings an
insect
in a box to a
natural history
museum. He asks an expert "What is this?" The expert says "You mean, apart from it being a
beetle
?" When the boy nods, the expert looks at the insect under a magnifying glass, or a
binocular microscope
. Chances are, it is a common beetle, and the expert can give the boy quite a lot of information about it.
But if it is not known to the expert, a much longer study is needed. Large reference books will be consulted; trays of similar insects will be taken out of store to be compared. A full diagnosis needs at least the
genus
and
species
. If the species is unknown, the detailed work of description is needed for publication.
Mostly, in biological
taxonomy
, the
adjective
"diagnostic" is used for any distinctive
trait
which places the specimen in a precise category. For example, A single bone making up the lower jaw is
diagnostic
of a
mammal
.
"Diagnostics" is the name given to procedures which spell out what to do to find the cause of a fault. This term is used a lot in
computer systems
.
