Re: Do You Write in your Reference Books?
Almost never; something in our this-life upbringing (or a lot of somethings, I suspect) put us in the camp where altering a book is seen as damaging it. Unless it's past saving anyway, in which case, art supply~!
We do, however, have a copy of a collection of Jung's works on active imagination in which we see a lot of useful material in terms of our shamanistic work, and in which we've taken to writing marginalia...mostly about how it parallels works that are explicitly about shamanism, and in some cases our experience of plurality. I think we might do the same with other books that cross fields of study or bring a new dimension to what we've already been doing. "Hey look at this" stuff is more likely to get a poor man's bookmark of some kind, or if we're making serious business of it, a book dart so that we can mark the exact line of interest. Highly recommend book darts if you're in the anti-marking camp; in the US, you can find them at Borders...not sure offhand if B&N carries them.
"All knowledge is worth having." -Phedre no Delaunay
"Everything has a price." -Jaenelle Angelline
"I think if you try, that's being your best." -Echo