No other letter in the English alphabet has such affectations, so I’m wondering why those two letters do. They’re not even necessary to distinguish the letter from another. Any real reason for them?
They’re not needed to distinguish them from other letters now. Before printing, though, there were a lot of letters that ended up looking like little bumps or spikes (m, n, r, i, l) and there needed to be ways to distinguish them from each other. It helps, also, to remember that “j” actually comes from “i”. Originally, they were pronounced the same (Latin “Iuvenal”, whom we now call “Juvenal”), but in most initial cases the “i” began to develop a palatalized sound, and the change was made to distinguish that.
This is all from memory, so details may be wrong…
How easy is it to distinguish J from j without the dot in the latter case? How about I from i? (especially if you’re going san serif)
That’s just silly. How dissimilar are S and s, or U and u? jayjay’s halfway there - as with just about every distinguishing feature of printed text as we are familiar with it, it’s a hangover from early printing, which itself took on many features of manuscript techniques. Something that was necessarily simplified was the system of diacritics - symbols added to letters changing their function or pronunciation. Dots, slashes, all sorts of marks were added to various letters. Plenty survive in some languages, but the true mongrel that is English lost them all. The dots on I and J are impotent decorative remains.
Ok, I’m not sure if this is relevant at all-- perhaps a Dutch person can come in and clear this up, but in modern Dutch you have the letter, basically, “ij”-- an i and a j in a pairing-- while there are i’s and j’s that appear by themselves, the ‘ij’ set is so frequent that it gets a spot in the dictionary and a scrabble tile (in Dutch scrabble, that is). This ‘ij’ set, though, in older writings, often appears cursived-together, basically as a ‘y’ with an umlaut (up as late as 19th c) (and in fact as I think of it the places where they use this ‘ij’/y-umlaut are about the same as where ‘y’ appears in English in cognates-- i.e. bakery would be bakerij). I wonder if the English i and j usage relates to this older Germanic usage with umlauts?
Other possibility/ in addition, I think JayJay has a point-- in Carolingian minuscle, e.g., things start to look very similar-- loops and points and such-- you know like how you loose track of things in someone else’s cursive with a lot of m’s and n’s and u’s and w’s? Without dots things might have been much worse, pre-printed type. Not as much of a problem with the capital letters, which look different from the other letters. Ever try to read cyrillic cursive, or someone’s German handwriting, where bumps and valleys reverse from our American manner? Imagine trying to read cursive words like ‘ummnium.’
The reason is clearer if you can use the type of writing that is similar to what the monks used. My English professor used the Latin word “minim.” I can’t really do this in ASCII or the font here, but in the style of the day, each downstroke was identical. In addition they were all connected and spaces were only used between words. The effect was something like this:
IIIIIIIIII
Three downstrokes for the “M”, One for the “i”, two for the “n,” one for the next “I” and three for the final “M.”
So they added the dots:
IIIiIIiIII
A bit easier to decode.
When the letter j was added, it kept the dot from the i.
I’m no expert on medieval Latin paleography, but I’ve seen enough manuscripts to be sure this explanation is way off the mark. There’s too many other combinations of vertically-oriented letters for these two letters alone to have acquired identifying marks - ‘unum’, for example, would equally become a series of vertical lines. And in any case, there’s far too much use of abbreviations and diacritics for such a consistent use of dots on I and J to be explained by this alone.
I was simplifying and was unable to actually draw the letters. But the U was formed by upstrokes, while the M, N, and I were formed by downstrokes. Think of them as slashes (for the upstroke) and backslashes (for the downstroke).
Thus “Unum” would be:
/ / \ \ / / \ \ \
This is decipherable.
However “minim” would be a problem:
\ \ \ \ \ \ \ \ \
The dots would differentiate (I’m using o to make it clearer, and they aren’t centered absolutely accurately):
o o
\ \ \ \ \ \ \ \ \ \
Thus you can now better understand the letters.
Did every manuscript use this system? Certainly not. But it was a useful tool and eventually became the general rule.