To any professional type designer, it's a terribly balanced font aesthetically, basically every letterform. It looks like a font designed by an engineer, not a designer who knows how to create and balance shapes and lines that are pleasing and easy to the eye. Which, of course, is exactly what it is.
This is exactly why I like it. Designed by an engineer for the purpose of typesetting engineering articles and books.
Most of the other alternative fonts feel like they were designed by a designer with all the unnecessary flairs that would make a great title/heading font to pad the portfolio but are needlessly distracting in a paragraph of dense technical text interspersed with equations.
Keep in mind that Google / Facebook / Twitter / Apple / Microsoft / etc hire hordes of professional designers and the result is a horrible user experience for everyone. I much prefer Wikipedia and Hacker News to most "modern" web design by professionals.
Serious alternatives were designed by foundries decades or even centuries ago.
I'm talking about good sense of aesthetic proportion and balance, not "flair".
And what exactly is the horrible user experience that Google has created with Roboto, or Apple with San Francisco, or Microsoft with Calibri? They're actually quite excellently balanced and pleasing fonts for their purposes.
> not a designer who knows how to create and balance shapes and lines that are pleasing and easy to the eye
"Your subjective opinion of the font is wrong, because you're not an expert." If OP and GP (and honestly, most people I know) like the font, how is it not pleasing to the eye? What does it mean for the "aesthetics" to be "_terribly_" balanced?
It's true there's no reference manual for the equations for pleasing shapes, because however our preferences are expressed in our brain, we haven't been able to decode.
But to give one example to your question: the serifs in Computer Modern are thicker than the thin stems of letterforms. That's ugly, full stop. It's not balanced -- the proportions of thicknesses is backwards. The entire function of serifs is to taper and/or finish, never to add weight.
Or another: the loop (lower part) of the double-story lowercase "g" simply extends way too far to the right. It makes the letter feel like it's going to tilt and fall over to the left. It's not balanced, period.
So these are just two examples of terrible balance. Does that hopefully answer your question in a way that isn't an appeal to authority?
Edit: curious why I'm being downvoted for this comment, when I'm just trying to answer the parent comment with actual examples.
And where cmr absolutely excels is the accompanying greek, math symbols and typesetting. Nothing else comes even close in getting it readable, pleasing and uniform.
That's frankly a very idiosyncratic take, and not one many professionals would agree with.
By that logic, toolbars with icons would become easier to use if their icons were all slightly off-center from each other -- which is very much not the case.
Part of reading legibility comes from the shapes of words, not letters by themselves. Generally speaking, we read words -- not letters. When individual letters are off balance or especially non-uniform, they draw attention to themselves rather than making the word coherent as a whole. This, of course, is one of the reasons why kerning pairs are so important.
Also, tapering isn't a "flourish" it's just how roman serifs work. And "uniform box of equal greying when smudged" is neither a flourish nor a rule at all, it appears to be something you've invented.
That's true of all serif fonts with thin stems, no?
1. Is this really true? I went to the bookshelf and pulled out three Knuth books, and at least to my eye, the serifs don't look noticeably thicker than the letter stems in the unbalanced way you mentioned. The exact proportions could be found by checking Volume E or generating proofs from the Metafont sources (haven't tried that), but this seems like the well-known problem with the "spindly" Type-1 versions of CM that many people use today, than in Knuth's actual Computer Modern as in his printed books. (See https://tex.stackexchange.com/a/361722/48 for pictures.)
2. Is this any worse in Computer Modern than in Monotype Modern, the typeface that Knuth was trying to reproduce? This is the font used for TAOCP Vol 1 first edition (1968), Vol 2 first edition (1969), Vol 3 first edition (1973) and Vol 1 second edition (1973). Those books were typeset with hot-metal typesetting (on Monotype machines), and in fact when Addison-Wesley approached Knuth in 1962 (when he was in grad school) to write a book, he was excited because he loved the appearance of their books. The publishers' move to phototypesetting could not recapture that look, and digital typesetting was starting to become feasible, so he took up the problem himself: he wanted to reproduce Monotype Modern so he needed TeX to typeset it, and Metafont to specify it (and Computer Modern was the result).
My guess is that the opinion you're expressing results from a combination of both the above:
• Yes, what Knuth was aiming for (Monotype Modern 8A, or the look of math textbooks he used as a student, or mathematical journals of a certain period: https://projecteuclid.org:443/euclid.bams/1183544082 ) was very much an early 20th-century / late 19th-century look, and it seems the fashion in contemporary typography circles (I suspect this started with William Morris in the 19th century already) to look down on that period and all that it entails (like larger spaces between sentences: witness Bringhurst's comments about "In the nineteenth century, which was a dark and inflationary age in typography and type design" etc). So, people au fait with modern typographical fashions don't quite like the associated style (Scotch Roman typefaces, etc), while many mathematicians quite prefer it.
• The poor Type 1 versions of Computer Modern cause the letter stems to appear thin, and even more so on low-resolution devices like monitors, causing the serifs to appear thicker in comparison.
Personally, comparing Monotype Modern (as in the first editions of TAOCP) and Computer Modern (in print, and using "true" CM), I don't think Computer Modern looks worse than the source typeface in terms of having terrible balance or appearing like "a font designed by an engineer"; the issue is probably more the "shared taste" you mentioned: Knuth's target aesthetic was itself different.
That said, the given justifications still seem subjective to me (why should serifs only taper? I actually like the added weight because it seems to emphasize the orientation of the letter. Why should fonts be scrutinized according to the laws of physics?).
I suppose to some degree the difficulty I'm having is what I view as an over-emphasis on objectivity in a discussion about aesthetics. Not that your perspective is wrong per se, but I find it hard to ignore the strong preference among my peers for choosing (and commenting positively on) this font.
In an extreme, one of my professors presented from notes and blew up his notes' display size like crazy, and I could never get a reasonably information-dense printout of those by printing multiple pages (those sizes were so large the fonts were too slim for the printer's resolution). Granted, it is an abuse of good typesetting, but I imagine my predicament would be helped with a font that had proper contrast.
It works pretty well balanced in print on systems it was originally targeted to. The main problem with using other fonts in TeX/LaTeX (or anything in, say, Word) is making it so complex equations lay out reasonably. Admittedly a niche problem, but one one that was the original purpose of TeX - and CM works well for it. There are a small number of other options that don't screw it up.
Most common typefaces are useless for mathematics, so it's a bit of an oranges and apples comparison anyway.
PDF copies also available on scribd: https://www.scribd.com/lists/2705622/Motion-Mountain-Collect...
It doesn't look bad, but I still don't think it quite works for dense paragraphs of text compared to Latin Modern. I do really like how it looks on the slideshow in a sibling comment, though.
http://soliton.vm.bytemark.co.uk/pub/jjg/pdf/vfplot-GUM11.pd...
Oh God, 10 years ago ...
But I stayed for the content. Interesting! And what a great presentation! I have so many questions. What happened to this in the intervening decade? Is the idea incorporated into any other plotting packages? Did you purchase this font to use in your talks?
> Oh God, 10 years ago ...
I know that feeling.
The package vfplot [1] is still available and still under development, it's rather hard to use in that there are lots of parameters to adjust to get decent looking output. There's also an issue in that the "dimension climbing" approach means putting an ellipse at each boundary corner and then as many as you can fit on the line-segment between them, there are lots of ways that this can fail for complex boundaries (coastlines, for example). I think I've fixed this using the fact that "a line segment is a degenerate ellipse", so one can actually calculate a "distance" between a line-segment and an ellipse in almost the same way as one calculates the distance between ellipses. The code for this is in a branch on GitLab [2], but there is still quite a bit of work to do for the 2.0 release (later this year?).
[1] http://soliton.vm.bytemark.co.uk/pub/jjg/en/code/vfplot/
https://skemman.is/bitstream/1946/7418/1/MSc_Arnar-Birgisson...