There are a few words which I blank on quite frequently. Perhaps my "advanced" age has something to do with it. I don't know. One such word for me is euphemism.
There is another word I am blanking on right now. In my answer to this question I also blanked on the same word.
It is a word which describes the power of a quotation, or memorable words, or a theory to stimulate further thought and perhaps research. The word is similar in meaning to prolific, which can denote having the power to generate many further thoughts and ramifications of the original quotation, words, or theory.
If you would be so kind as to supply this word for me and perhaps give me a mnemonic device to make it accessible to me, I'd be very grateful.