Classes and intelligence

[Inevitability]

I've seen people state animals can't take class levels because of their low intelligence several times. Is this an official rule? Is it stated anywhere creatures need at least 3 intelligence for taking class levels?

Note that I'm talking about a monster, not a player. LA is no issue.

[sideswipe]

I've seen people state animals can't take class levels because of their low intelligence several times. Is this an official rule? Is it stated anywhere creatures need at least 3 intelligence for taking class levels?

Note that I'm talking about a monster, not a player. LA is no issue.

well a PC can have a int of 1 and still function in its class (unless int caster), you can even start with an int of 1, just naturally for most player races it cannot go below 3, adjustments can make it less.

using that logic, i don't see why an animal cannot take class levels once its HD advancement has reached its peak. though the hard point would be what classes could it take? it would probably have to be gifted them from something.
i cant imagine a wizard polarbear, but a favoured soul of one of the nature gods with eshew materials and silent and still spell? cant see why not. (or some cheese to allow casting them without the +2 to each spells level).

edit - just looked through the monster manual, there it says nothing about non intelligent or low intelligence creatures not being able to take class levels, just suggests a little (not even heavily) that HD advancement is better for non intelligent things.

[Sliver]

A PC can't really have Intelligence under 3... This appears several times in the rules:


[...] creatures with an Intelligence score lower than 3 are not playable characters

[Inevitability]

A PC can't really have Intelligence under 3... This appears several times in the rules:

Yes, but how about monsters with class levels?

[Curmudgeon]

I've seen people state animals can't take class levels because of their low intelligence several times. Is this an official rule?
The only relevant rule is whether class levels are allowed, as specified in the creature's Advancement entry. Example:
Advancement: 3–5 HD (Medium), 6–10 HD (Large), or by character class If the Advancement doesn't call out something like that highlighted part, you can't advance by character classes.

Here's the relevant section from READING THE ENTRIES in Monster Manual (page 7):
Advancement
This book usually describes only the most commonly encountered version of a creature (though some entries for advanced monsters can be found). The advancement line shows how tough a creature can get, in terms of extra Hit Dice. (This is not an absolute limit, but exceptions are extremely rare.) Often, intelligent creatures advance by gaining a level in a character class instead of just gaining a new Hit Die. So there's a correlation, but not an explicit rule, that character class advancement is tied to Intelligence. You have to look at each monster entry to find out the specifics (what's allowed for each creature).