"Or, if there were a sympathy in choice,
War, death, or sickness did lay siege to it,
Making it momentary as a sound,
Swift as a shadow, short as any dream,
Brief as the lightning in the collied night,
That, in a spleen, unfolds both heaven and earth;
And ere a man hath power to say "Behold!"
The jaws of darkness do devour it up:
So quick bright things come to confusion."
--Lysander from Act 1, scene 1, 141–149, "A Midsummer Night's Dream"
This is that talk we need to have on the last term in the Drake Equation, mostly commonly denoted as "L". I'd like it to be more of a conversation than a soliloquy, so please share your thoughts here, or come on over to the G+ Community and let me have an earful. Better yet, let's talk in real time, and record our conversation for the Wow! Signal Podcast.
I would also like to point out that Seth Shostak has written thoughtfully about "L" in this document (go to page 399), and covers many of the key points well. Perhaps you should read that first. I'll wait.