What do each of the three primary attributes affect?

Solution 1:

When increasing your stats (might, finesse, brains) they will increase their derived skills (skills that use same symbol as that stat).

Formula = ("Base Stat"/5) is added to a derived skill when you use it.

Might will also add 6 extra inventory slots for every 10 points put into it.

Skills each attribute affects:

Might :

  • Blade
  • Knife
  • Mechanical
  • Melee

Finesse :

  • Assault Weapon
  • Electronics
  • Heavy Weapon
  • Lockpick
  • Pistol
  • Rifle

Brains :

  • Biotech
  • Computer
  • Decipher
  • Foraging
  • Medical

Solution 2:

In addition to affecting the skills associated with the stat (identified by the icon), the three stats also have the following effects (straight from the manual):

Might

Dictates the strength and resilience of the player. It increases the size of your Inventory, your resistance to poisons, your ability to avoid getting grabbed, and the amount of food you can eat to avoid starvation.

Finesse

Dictates the coordination of the player, and while it mostly acts on associated skills, it does help counter certain conditions, such as blindness.

Brain

Dictates the smarts of the player, and while it mostly acts on associated skills – particularly those involved in hacking and repairing machines - it does help counter certain conditions, such as confusion.

Solution 3:

Might

Each point of Might increases food capacity by 10 and base ability to shrug off the most common status ailments such as Disease, Poison, Stun, and Grabbed.
Every 10 points of Might will increase inventory size by 6.
Every 5 points of Might will improve the following (4) skills by 1 ; Mechanical, Blade, Spear, Melee.

Finesse

Each point of Finesse increases your resistance to a few vision-impairing status effects, such as Blind.
Every 5 points of Finesse will improve the following (8) skills by 1 ; Lockpick, Electronics, Pistol, Rifle, Assault Wpn, Heavy Wpn, Knife, Traps.

Brains

Each point of Brains helps you detect Floor Traps before you step on them, and helps resist some mind-addling status effects such as Confusion.
Every 5 points of Brains will improve the following (6) skills by 1 ; Computer, Engineering, Decipher, Medical, Foraging, Biotech.
Each point of Brains also increases the amount of Psi Points at your disposal by 1 per point.

Power

Better designated as Psi Power, each point of Power increases the strength/effectiveness of your Psi Powers.
Each point of Power increases psi point capacity by 2.
Each point of Power helps negate or diminish the effects of certain psionics like Fear, Paralyze or Drain Life.
Unlike the other stats, Power does not directly increase any skill's points.

The skill bonuses due to Stats have a natural limit of 20 (i.e. the stats can go as high as 100, and give 1 skill point per 5 points in a stat, hence 20) and these bonuses allow skills to go above their normal limit of 100.