It is complicated.
> Where "certain" means "specific" or "particular", the two sentences
> essentially mean the same thing.
But in the construction "a certain [something]" "certain" does not normally
mean "specific" or "particular"; it means "I the speaker might know what
the something is, but I choose not to tell anyone".
The example with "specific" suggests that the reporter isn't going to tell
us the readers, but did give precise details to the person they were
talking to.
> They mean that Joe's garage is the only
> one that can do that type of repair (well, maybe not the only place, but
> certainly the best in the neighbourhood).
"Had to go" means no choice or flexibility. It is the past tense of
"must go". The going or the destination or both were compulsory, not
voluntary or optional.
> On the other hand, although it's a little obscure, in (a) "certain"
> could also mean "sure, "permanent", "perfect", "confident" etc - in
> which case there is obvious that the sentences are different.
OED agrees that "certain" can be confusing. (Sorry for the huge cite
below, but who am I to argue with the OED if they think it necessary?)
"certain, adj., n., and adv.". OED Online. March 2013. Oxford University
Press. 26 May 2013 <
http://www.oed.com/view/Entry/29975>.
II.
7.
a. Used to define things which the mind definitely individualizes or
particularizes from the general mass, but which may be left without further
identification in description; thus often used to indicate that the speaker
does not choose further to identify or specify them: in sing. = a
particular, in pl. = some particular, some definite.
Different as this seems to be from sense A. 1, it is hardly separable from
it in a large number of examples: thus, in the first which follows, the
hour was quite ‘certain’ or ‘fixed’, but it is not communicated to the
reader; to him it remains, so far as his knowledge is concerned, quite
indefinite; it may have been, as far as he knows, at any hour; though, as a
fact, it was at a particular hour. (The absolute uses are in B 4–6.)
138. Wyclif Wks. (1880) 220 How religious men should kepe certayne
Articles.
1393 J. Gower Confessio Amantis II. 16 A certain ile, which Paphos Men
clepe.
a1400 (▸a1325) Cursor Mundi (Vesp.) l. 8933 Ilk dai a certain hore,
þar lighted dun of heuen ture Angels.
1483 Caxton tr. J. de Voragine Golden Legende 242/1 Saynt domynyk spak
to the pryour..of certeyne mater.
1526 Bible (Tyndale) John xi. 1 A certayne man was sicke, named
Lazarus.
1572 in A. Feuillerat Documents Office of Revels Queen Elizabeth (1908)
411 A note of sarten thinges.
1578 H. Lyte tr. R. Dodoens Niewe Herball ii. v. 152 The rootes
be..covered with certayne scales.
1600 L. Lewkenor tr. A. de Torquemada Spanish Mandeuile f. 18v, Theyr
garments are made of a certaine fine woll, like Bombast.
c1600 Wriothesley's Chron. Eng. (1875) I. 61 In Aprill 1536, certen
comyssions were sente into the weste countrye.
a1616 Shakespeare Measure for Measure (1623) v. i. 129 For certaine
words he spake against your Grace.
1651 T. Hobbes Leviathan ii. xix. 94 Not every one but Certain men
distinguished from the rest.
1710 R. Steele Tatler No. 173. ⁋3 There are certain faces for certain
Painters, as well as certain Subjects for certain Poets.
1711 J. Addison Spectator No. 37. ¶1 A Letter..directed to a certain
Lady whom I shall here call by the Name of Leonora.
1744 G. Berkeley Siris §1 In certain parts of America, Tarwater is
made.
1805 Med. & Physical Jrnl. 14 437 The Reports which certain public
associations have circulated.
1856 J. Ruskin Mod. Painters III. 73 Everything that is natural is,
within certain limits, right.
1875 W. S. Jevons Money (1878) 5 If a certain quantity of beef be given
for a certain quantity of corn.
1879 M. Arnold Equality in Mixed Ess. 65 Certain races and nations, are
on certain lines pre-eminent and representative.
1887 (Police Notice) ‘Whereas certain persons unknown did, on the night
of.., feloniously enter’, etc.