Discussion Groups / British English / April 2005

No.  There are pairs, like "politic"/"political",
"historic"/"historical", where the meanings differ.  There are also
pairs, like "ironic"/"ironical", "problematic"/"problematical", where
it does not.  There is a suggestion that -ic is more American and
-ical more British.  Often, a form in -ical correlates with a word in
-ic (music <-> musical; topic <-> topical), whereas a form in -ic
correlates with a word in -y (economy <-> economic; comedy <->
comedic).  Words in -ics tend towards -ical (ethics <-> ethical;
statistics <-> statistical) unless -ic arose first (acoustic ->
acoustics; phonetic -> phonetics).  Historically/etymologically there
has been crossover between forms, aided by the common form of the
adverb in -ically.