Posted on February 17, 2008 by Alex Poole

Back in 1998 when Times New Roman was still widely used on the web, my then boss made sure we always designed our web sites with Arial, as she hated the look of serif fonts on the web. Was it the case that sans serif fonts were more legible, or was it just a matter of taste?

In 2003 as part of my master’s degree I reviewed over 50 empirical studies in typography and found a definitive answer.

Arguments in favour of serif typefaces Serifs are used to guide the horizontal “flow” of the eyes; The lack of serifs is said to contribute to a vertical stress in sans serifs, which is supposed to compete with the horizontal flow of reading ( De Lange et al., 1993 )

These are the most common claims when trying to make a case for the utility of serifs. However, serifs cannot in any way be said to “guide the eye”. In 1878 Professor Emile Javal of the University of Paris established that the eyes did not move along a line of text in one smooth sweep but in a series of quick jerks which he called saccadic movements (Spencer, 1968, p. 13 ; Rayner & Pollatsek, 1989, pp. 113-123 ). Unfortunately many graphic designers and typographers continue to use this rationale for the existence of serifs, due to a lack of communication and cooperation with the research community.

Serifs are used to increase spacing between letters and words to aid legibility

Serifs are not required to control letter and word spacing – in fact, serifs would be woefully inadequate for this purpose. In traditional letterpress systems, spacing is achieved with small pieces of metal inserted between the letters, and by the spacing between the letter form and the edge of the print block. Spacing is even easier to manipulate with modern computerised typesetting equipment. ( Sassoon, 1993 ; Rubinstein, 1988 )

Serifs are used to increase contrast (and irregularity) between different letters to improve identification

Well established research has shown that whole words can be recognised just as quickly as letters during an eye fixation and that single letters can be identified quicker when embedded in a word. Such a ‘Word superiority effect’ would indicate that serifs are not needed for distinguishing between single letters ( Reynolds, 1979 ).

Serifs are used to bind characters into cohesive ‘word wholes’

The simple Gestalt created by spaces between words would be enough to bind letters into ‘wholes’. Furthermore, other features such as character ascenders and descenders should have a much greater effect on word recognition than serifs ( Poulton, 1965 ).

Readers prefer body text set in serif typefaces, so they must be more legible

Many studies conducted in the past did indeed find a preference for serif typefaces (Tinker, 1963 ; Zachrisson, 1965 ). However, Tinker commented that perceived legibility was due to a great extent to familiarity with the typeface. 40 years ago sans serif typefaces were not as common as they are now, and if these studies were repeated, it would not be surprising to find completely different results. Indeed, more recent studies have shown that computer users prefer sans serif typefaces for body text online ( Boyarski et al., 1998 ,Bernard et al., 2000-2001 , Tullis et al., 1995 , Reynolds, 1979 ).

What is important to bear in mind is that in almost all legibility studies, reader preference or perceived legibility tends to be inconsistent with user performance ( Lund, 1999 ).

Serifs are used for body text because sans serif causes fatigue

It is often claimed that reading large amounts of body text set in sans serif causes fatigue, but there is no evidence to support this, as measuring fatigue has not been a concern in the vast majority of legibility research comparing serif and sans serif typefaces.

Furthermore, “no satisfactory objective method of measurement has been devised. Subjective assessments of fatigue are subject to modification by a great many factors which may be totally unrelated to the experimental situation”. ( Reynolds 1979, p313 )

Arguments in favour of sans serif typefaces Serifs are just an historical artefact

This could be true to a great extent, especially since claims attempting to justify serifs in retrospect have been less than convincing.

Many researchers attribute the origin of serifs to the Romans, some claiming that “Roman masons … terminated each stroke in a slab of stone with a serif to correct the uneven appearance made by their tools”. ( Craig, 1980; in Bix, 2002 ). Others state that “design by brush before execution in stone gave rise to … tapering serifs at the terminals of many strokes”. ( Bigelow, 1981; in Rubinstein, 1988, p10 ).

What ever their origin, serifs have been around for so long that perceived legibility is very likely to have been affected by familiarity – readers tend to rate as more legible the typefaces they are most used to ( Tinker, 1963 ; Zachrisson, 1965 ).

Sans serif are better on the web

Although studies of screen reading show no difference between reading from screen and from paper ( Dillon, 1992 ; Bernard, 2001 ), there could be some validity to this argument.

When typefaces are digitised for use on computers, the letter forms have to fit within a relatively small pixel grid, often leading to what are called the “jaggies” ( Rubinstein, 1988). Many web professionals such as graphic designers claim that this relatively low resolution cannot render effectively enough the fine finishing strokes of serif typefaces, and that sans serif typefaces lend themselves more naturally to being digitised, and come out cleaner and thus more legible.

However, this has not been borne out by recent evidence ( Bernard, 2001 , Boyarski et al., 1998 , Tullis et al., 1995 , De Lange ), that shows no difference in legibility between serif and sans serif font on the web.

Sans serif is better at small sizes. Sans serif fonts survive reproduction and smearing because of their simple forms

Some research has shown that serifs may actually become visual noise at very small sizes, detracting from the main body shape of the letter form ( Morris, et al., 2001 ). However, this has not been confirmed in tests of continuous reading ( Poulton, 1972 ). Other factors such as stroke thickness, counter size and x-height are likely to have a far greater effect in preserving the overall identity of a letter form whether it be through smearing or size reduction ( Poulton, 1972 ; Reynolds, 1979 ).

Sans serif is better for children learning to read

Books produced for children are often printed with sans serif text as teachers claim that the simplicity of the letter shapes makes them more recognisable ( Coghill, 1980) , Walker, 2001 ). But studies with child participants have found no difference in their ability to read either style of typeface. ( Coghill, 1980) ; Zachrisson, 1965 , Walker, 2001 )

3. Conclusion

What initially seemed a neat dichotomous question of serif versus sans serif has resulted in a body of research consisting of weak claims and counter-claims, and study after study with findings of “no difference”. Is it the case that more than one hundred years of research has been marred by repeated methodological flaws, or are serifs simply a typographical “red herring”?

It is of course possible that serifs or the lack of them have an effect on legibility, but it is very likely that they are so peripheral to the reading process that this effect is not even worth measuring ( Lund, 1999 ).

Indeed, a greater difference in legibility can easily be found within members of the same type family than between a serif and a sans serif typeface. ( Tinker, 1963 , Zachrisson, 1965 ). There are also other factors such as x-height, counter size, letter spacing and stroke width which are more significant for legibility than the presence or absence of serifs.Poulton, 1972 ; Reynolds, 1979 )

Finally, we should accept that most reasonably designed typefaces in mainstream use will be equally legible, and that it makes much more sense to argue in favour of serif or sans serif typefaces on aesthetic grounds than on the question of legibility. ( Bernard, 2001 ; Tinker, 1963 )

By: Michael Beirut
Design Observatory, 8/9/2012 

I know in my heart that graphic design is important. Sometimes the fate of nations depend on it, sometimes it’s the missing link between a soft drink brand and Einstein’s Special Theory of Relativity, sometimes it just makes you happy. But I also know that the ingredients used by graphic designers — colors, shapes, typefaces — are fundamentally mysterious. What do they mean? How do they work? Why does one work better than another? What criteria should we use to choose?

This ambiguity can be maddening, especially to clients, who in desparation will invoke anecdotes and folk wisdom to help control an otherwise rudderless process. I’ve been told in meetings that triangles — to take one example — are the “most energetic” (or the “most aggressive”?) shape. I’ve been asked if it’s true that white means death in Japan. Or is it black? Or red? Or China? 

To tell you the truth, I’ve always appreciated this ambiguity. Like other experienced designers, I appear to navigate this miasma of hearsay with confidence. For the truth is that in our field, to quote screenwriter William Goldman, “Nobody knows anything.” Black can be ominous or elegant. Triangles can be trendy or timeless. And typefaces? Hmm! Typefaces can be…anything you want them to be, right? There are many reasons to pick any one typefaces, all of them more or less arbitrary. 

So imagine a client demands that text be set in “the most credible typeface.” I would probably hide a smile and say there’s no such thing.

But there is such a thing, says Errol Morris.

Several weeks ago, Morris, the Academy Award-winning documentary filmmaker and author, posted a simple quiz in his New York Times Opinionator blog. Ostensibly, the object of the quiz was to determine if the reader was an optimist or a pessimist. You read a short introduction about the likehood of an asteroid hitting the earth, and then an indented passage from a book by David Deutch, The Beginning of Infinity, in which he claims “we live in an era of unprecedented safety” and will likely be able to defend ourselves against such an impact. Morris then asked the reader to agree or disagree with the truth of that claim, and to indicate the degree of confidence the reader had in his or her conclusion. The result, supposedly, was to determine how many of us are optimists (finding Deutch’s statement to be true) versus how many are pessimists (finding the statement to be false).

But it was all a trick. Morris was actually testing something completely different: the effect of fonts on truth. “Or to be precise,” as he points out in his followup post today (part 1, part 2), “the effect on credulity. Are there certain fonts that compel a belief that the sentences they are written in are true?”

To find out, he had a colleague, Benjamin Merman, create a program that changed the font of the indented David Deutch passage each time the article was first opened. Each person taking the quiz would read the passage in one of six randomly assigned fonts: Baskerville,Computer Modern, Georgia, Helvetica, Comic Sans, or Trebuchet. So the test had nothing to do, really, with optimist or pessimism. Instead, it was meant to find out if setting the passage in one typeface or another would lead people to believe it more.

Now, if you’re like me, you already know what the least trustworthy typeface is, right? It’s got to be Comic Sans: goofy, unloved, mocked Comic Sans. And it turns out we’re right. According to Morris, people seem to be consciously aware of Comic Sans: it was in the news as recently as a few weeks ago, when it caused a minor dustup in the midst of the announcement of the discovery of the Higgs-Boson particle. This awareness seems to engender, in Morris’s words, “contempt and summary dismissal.” And good riddance, say I and countless other graphic designers.

But what about the other side of the equation? Is there a font that inclines us to believe that a sentence that’s set in it is true? After analyzing the research, Morris says the answer is yes. And that typeface is Baskerville.

To Morris’s surprise, the results of the test showed a clear difference between the performance of Baskerville and other fonts — not just Baskerville and Comic Sans (no contest); or Baskerville and Trebuchet or Helvetica (a clear serif versus sans distinction); but even Baskerville and Georgia (a lovely, and arguably even more legible serif by Matthew Carter). Compared to versions in the other typefaces, the passage set in Baskerville had both the highest rate of agreement and the lowest rate of disagreement. This led Morris to the inevitable conclusion: Baskerville is the typeface of truth.

John Baskerville loved typography, and it’s believed that he lost his fortune in pursuit of it, sinking all the money he had into designing and printing complete editions of the works of Virgil and Milton, not to mention the Bible. He was an avowed anti-religionist but had a deep and abiding faith in typography. “Having been an early admirer of the beauty of Letters,” he wrote in his introduction to Paradise Lost, “I became insensibly desirous of contributing to the perfection of them.” The typeface we today call Baskerville is based on the fonts he developed in the mid-eighteenth century at his foundry for his private presses. Ironically, a skeptic has created the typeface most likely to induce credulity.

“We have entered a new, unexpected landscape,” Errol Morris writes at the conclusion of his article. “Truth is not font dependent, but a font can subtly influence us to believe that a sentence is true. Could it swing an election? Induce us to buy a new dinette set? Change some of our most deeply held and cherished beliefs?”

Whether or not a typeface can do any or all of those things, I do agree the landscape has changed. Once upon a time, regular people didn’t even know the names of typefaces. Then, with the invention of the personal computer, people started learning. They had their opinions and they had their favorites. But until now, type was a still matter of taste. Going forward, if someone wants to tell the truth, he or she will know exactly what typeface to use. Of course, the truth is the truth no matter what typeface it’s in. How long before people realize that Baskerville is even more useful if you want to lie?