Brains

'Brains' is a Stat that affects various skills requiring you to be 'smart'.
Medic, Hack, Repair, Science, Linguist, Chemistry, and Teach are all skills that rely solely on Brains, checking no other stat.
The Brains stat is also used feint in combat. When your Brains stat falls below a certain point you will get a filter which will make you sound like the retard you are.

Skills that depend on Brains

Appraise
Bombs
Chemistry
Craft
Hack
Linguist
Locksmith
Medic
Persuade
Pilot
Repair
Science
Teach