<prompt> Human: I had 17k in student aid debt about 18 months ago, and I now have 1.5k. There are 4 roughly equal loans left at the moment, 3 at 6.8 and one at 4.5. Ive heard that paying debts off too quickly can lower credit, so should I just pay it all off or pay off the 6.8s and leave the 4.5 and pay it off super slowly? That seems silly to me, but I figure I should ask before the debt is gone.Also, are there any lazy ways to earn credit? Like a credit card that has each transaction paid off without me having to lift a finger. I currently dont have one, except for one I got from a retail store several years ago that I never use. Should I cancel that one?I think my current credit score is 740, from what I can tell. I wont be needing to take out a loan anytime soon, but Id like it to be as high as possible for when I eventually need it.  <response>: Dont pay interest to build credit. Get a credit card. Put one recurring bill on it a month. Set auto pay to pay it in full each month. Just let it cycle. About as lazy as you can get. 