They're both as diverse as eachother really, as Maths is used everywhere, but Psycology is a HUGE subject. You more often than not have to do a masters to specialise in a particular area of Psycology before your skills can be put to much use in the real world, so it could actually mean more as you often have to put in a lot more work.
As other people have said, i'm pretty sure you know nothing about the subject. I used to have pretty much the same opinion as you when i was in sixth form, that Socialogy and Psycology are useless subjects.
Learn a bit about something before you create a thread about it.