Oni said:
Because it doesn't work, at least your interpretation a couple of pages ago it seems (correct me if I've misunderstood you). The reason it doesn't work is this, you want to say someone that is deficient in the skills of literacy and numbers is unintelligent. Ignorance of a skill or fact has absolutely no baring on a persons mental capacity.
Let's assume that compulsory education in Australia, the EU and North America is, by and large, a reality. Clearly, everyone in our society is offered the opportunity to develop literacy and numeracy skills (though of course not equally). How and whether they develop them will, of course, vary based both on the quality of training offered and on the individual's interests in addition to innate talent.
Also note: I'm not arguing that intelligence is an innate characteristic; there is an innate component but ultimately,
any definition of intelligence is also going to be based on measurable skills. Given that no skills are wholly innate, clearly learning/skill development will always be a component of intelligence.
Let's assume we're having this discussion about strength or dexterity. Clearly, these attributes are also a hybrid of innate talent and some degree of learned skills. We call someone strong based on various skills (e.g. bench pressing), performance of which is based, in part, on innate talent and, in part on training. We call someone dextrous based, let's say, on the ability to catch a thrown ball; obviously innate talent is not the only factor there -- playing catch habitually would be pretty important too.
We have a problem when we discuss intelligence today because we want to find some kind of culturally transcendent measure of mental capacity. Guess what? We won't find one. Our measure of intelligence can only be effective within a culture, not across cultures.
As far as I can tell, the only D&D attribute which one could argue as culturally transcendent is wisdom. Every other attribute is a hybrid of innate talent and skill development. I don't think it's any surprise, then, that wisdom is also the attribute hardest to quantify in any remotely objective way.