# Using text figures in technical and scientific documents

Many sources, such as Bringhurst and other style guides, recommend using text figures everywhere except all-caps text. This would seem reasonable for documents containing a lot of regular text, such as books and novels. But how much does this recommendation hold for documents that contain a lot of math formulae intertwined with text, such as textbooks and scientific reports? Of course, using text figures in math proper is wrong, but what about text figures in text and lining figures in math? Is it better/worse than using lining figures everywhere?

• @Mortimer: en.wikipedia.org/wiki/Text_figures Mar 1, 2011 at 14:24
• @a-v: It's mostly a matter of taste. People aren't really used to text figures in math related texts, but it's perfectly OK to use them as long as you do what you already mentioned in your question: Make a strict separation between text and math, and always use lining figures for math. Mar 1, 2011 at 14:30
• @a-v If you are not bound by a publisher's style do your own experimentation. A book must reflect its individuality. Personally I like "old style figures", but not with heavy related maths texts. Mar 1, 2011 at 15:56
• @hendrik-vogt It actually becomes more interesting with inline math. If lining figures are used for that, then $x = 1$ will differ from Fig. 1. If, in contrast, we restrict lining figures only to display math, then $\sqrt{1}$ etc. inside a paragraph become odd. Mar 1, 2011 at 16:35
• @a-v: Please use "@Hendrik" to ensure that I get notified (note that there's no "-" in my user name). Concerning your comment: When I wrote "strict separation", I meant that you should use lining figures for all math, so that $x = 1$ will indeed differ from Fig. 1. This may not be so nice, but I see no way out of it. Having inline and display math look diffent is much worse. Mar 1, 2011 at 17:56

It's mostly a matter of taste. People aren't really used to text figures in math related texts, but it's perfectly OK to use them as long as you do what you already mentioned in your question: Make a strict separation between text and math, and always use lining figures for math, i.e., for both inline and display math. This means in particular that the 1s in$x = 1$ and Fig.~1 will differ: