I once attended a workshop for Motorola employees on interpersonal relationships in the work place. The speaker wanted to make an impression on us that it is very important to consider how you say things as well as what you say. His example to demonstrate the difference in how the same message will received was:
- Honey, you have a timeless beauty.
- You have a face that could stop a clock.
I bring this up because it is oft said that Chazal don't gozer g'zeiros l'g'zeiros (do not make safety precautions on top of safety precautions). Yet, when confronted with examples that appear to be just that, the answer is usually, "Well... that's included in the original g'zeira." Is that just a way of saying the same thing in a more palatable format? (Hint: No; but we'll need to do some work to understand why not.)
One classic example is with respect to meat and milk. The Torah assurs cooking meat (cow/sheep/goat) with milk. Chazal made two g'zeiros: One not to eat fowl cooked with milk, one not to eat cold meat with cold milk. Using the rule of no g'zeira l'g'zeira, shouldn't I expect that eating a sandwich of turkey cold cuts with cheese whiz should be ok? Of course we know that is also assur; the question is why. (If you are holding by eating cheeze whiz, you are patur from mitzvos and probably drooling on yourself now.)
Another example (that I recently saw and is what prompted this TftD) is that the Torah assurs completing a keili (tool/utensil/clothing/...) on Shabbos. Chazal (see 299:7) made a g'zeira to not move a candelabra made of multiple pieces on Shabbos. The Rema, however, notes that even if it isn't made of pieces but just has grooves so it looks like it's made of pieces, then it is still muktzeh. Again, doesn't that seem like a g'zeira on a g'zeira?
The resolution is that there are two basics types of g'zeiros. There are g'zeiros to protect me from accidentally slipping into forbidden activities. Not reading by candlelight on Shabbos is an example. Chazal were protecting me; it is very easy to forget oneself while learning and reach to tilt the lamp. They did not, however, forbid me from picking up a book in front of a candelabra out of a concern that I might come to read and then I might come to tilt that lamp. That surely would be a g'zeira l'g'zeira.
Other g'zeiros, however, are to protect others from drawing the wrong conclusions about what is permitted when they see me doing something. The two examples above are in that category. When someone sees me eating a cold cut sandwich, they can't tell whether it's turkey pastrami or beef pastrami. When someone sees me moving a candelabra, they can't tell with it's really made of pieces or just has grooves that look likes it's made of pieces. Not a g'zeira to a g'zeira, but included in the original g'zeira to fulfill the original intent of that g'zeira.
I don't have a pithy ending, sorry.