The most I ever took was 18 credits. I think more than that would have been too much for me to handle. I usually had 16 credits, until my senior year, when I was done with all of my required courses and only took 12 credits to give me extra time on my senior thesis. But everybody's different. For some, more than 12 credits is too much. So, just start slow, and if you have no problem handling your 13-credit schedule, you might want to consider bumping up to 16 credits.
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Helinger: Now, what do you see, John?
Nash: Recognition...
Helinger: Well, try seeing accomplishment!
Nash: Is there a difference?