Provolution said:
There seems to be some policy disagreement here.
I heavily support going for currency as well.
The reasons are the following:
We built three libraries that are standing redundant after Republic is researched already. Gambling on when the AI will let us get currency through Great Library is a gamble, since that can take some time. Early Currency will garner us the following advantages:
Early Marketplaces with 50 % extra gold per city with marketplace.
Early Currency may give us a tradeable monopoly technology for gold, as we already got the research advantage with libraries (Notice our Nr 1. Literacy Rate)
Early Currency has the potential to give us a great leader
Early currency allows us to gear our commerce cities to gold production
Marketplaces provide extra luxury bonus for cities, to make them grow bigger
I urge all citizens to support this call for researching Currency, before we zero out slider to get, literally, some hard currency.
First off, thank you for posting this thread, as I have been thinking about this issue for awhile and would like to hear other's opinions (as I'm stumped

)
Next, some responses.
First off, I think that your arguments regarding the possibilites of a Great Leader and a luxury bonus aren't very strong, as the first is really a small-chanced gamble the second requires three luxuries in order to be in effect. With only one luxury now, one available from Rome upon the completion of a trade route to Rome, and one even visably remaining on the continent (and most likely to fall into Roman hands as well), I see the chances of recieving the second two luxuries needed to reap the benefits within a timely manner small.
What will really decide it for me is the short-term / long-term gain. Obviously the short-term will benefit from a 0% Science, as we would reap over 230 gold in the time that we could receive currency before going back to 0%.
However, in the long-term, the marketplaces will gain a 50% bonus in each city (as of right now, that is around 15 gpt total, and will be more as we grow). That means we would, after all marketplaces are in place, we would cover up that ground in no more than 15 turns. Of course, these marketplaces won't be in place directly after completing currency, but granary pre-builds will give us a very short turnaround time.
Now, here's another kicker. With Republic at our disposal, many people would most likely like to revolt right away. If this is done, our 20 gpt of support will be lost while researching currency, meaning at 100% we'd be at around -28 gpt! With this knowledge, it seems proper to assume that a currency-next attitude would mean holding off on a republic, finish Currency, revolt, finish marketplaces. It's tough to tell whether or not the Persians will send anything at us that will require us to need rush-building of units, so that will have to be something to be aware of. With the currency-next order, this means that we wouldn't be able to rush-build with gold for more than 20 turns.
Since we'll be at around 140 gold when Republic finishes (not counting the bonus for limiting the slider w/ zero turns left), to go 100% currency at around -8gpt for 10 turns would be unwise. I would find a 70% number more likely to work for 14 or so turns.
Still however, this is a long stall. The timeline of my previous comments could look like this:
Finish republic (4 turns) --> Finish Currency (14 turns) --> Revolution (5 turns) --> Catch up with gold lost with Marketplaces now in place (15 turns)
for a possibility of 40 turns total before we achieve equilibrium, and around 25 turns before we see a good income again. Perhaps this could be made up with trading currency, but this relies on the idea that foreign nations have a substantial amount of gold in their reserves, which currently isn't the case. (In 20 years though, who knows...perhaps we could be trading back for our own money...)
Now, this is only the path I would take, and I haven't checked my numbers too extensivly. Someone might come up with a better gameplan, and if they do I'd like to hear it.
Edit: With the knowledge that DZ has posted below, I'm now firmly towards the 0% side rather than the currency side. The idea of getting currency far later in game seems remote now, as a simple trade from France to any nation, or the chance that an ai will follow suit (and in less amount of turns due to the technology cost decrease), leads me to believe that we have nothing to worry about in terms of getting Currency far later.