On 9/3/10 9:38 PM, Dusko Pavlovic
speaking of coherence in closed categories, i was always under the impression that kelly and maclane, while writing their 1971 JPAA paper, and the later one (1979?) secretly drew string diagrams on the side, and then translated them into categorical diagrams. at least for counterexamples, this works. and in the kelly-laplaza paper about compact/autonomous categories: the free construction is expressed in terms of strings, but i guess at the time it was easier to describe them in words, than to wait for the publisher to typeset your stings for you.
In the earlier 60s, it wasn't conceivable to include even tree diagrams in anything to be published hence my inidicial approach to the formulas for A_\infty structures jim [For admin and other information see: http://www.mta.ca/~cat-dist/ ]