<prompt> Human: I received blank checks for a credit card I have with no balance that can be used for anything, even deposited into your account. The terms are: pay 3 up front, then 0 interest for 18 months.I am considering taking 10,000 out, buying VTSAX, holding it for 18 months and then paying the card back. What do you guysgals think? I cant see VTSAX returning less than 3 over the next 18 months. Is this a good or bad idea?If its a good idea to do this in general but theres suggestions for things other than VTSAX let me know about that, too.  <response>: Mate, no. Whether you and I can see the market dropping is immaterial. You should only invest what you can afford to lose. 