DSM says it's the following:
Quote:
Criterion A. Severe and sustained impairment in social interaction
Criterion B. The development of restricted, repetitive patterns of
behaviour, interests, and activities
Criterion C. The disturbance must cause clinically significant impairment
in social, occupational, or other important areas of
functioning.
Criterion D. In contrast to Autistic Disorder, there are no clinically
significant delays in language (eg: single words are used
by age 2 years, communicative phrases are used by age 3
years).
Criterion E. There are no clinically significant delays in cognitive
development or in the development of age-appropriate
self-help skills, adaptive behaviour (other than in social
interaction), and curiosity about the environment in
childhood.
Criterion F. The diagnosis is not given if the criteria are met
for any other specific Pervasive Developmental Disorder or
for Schizophrenia.
But then the diagnostic guidelines give a long list of things, and says it's any combination of several of them. The guidelines also make for possible diagnoses which sound much less drastic than the criteria above. For example, the "Severe and sustained impairment in social interaction" requirement can be met by, say, "failure to develop peer relationships appropriate to developmental level" and "lack of social or emotional reciprocity." So just wanting to be left alone for the most part, and succeeding in that wish, could qualify a person. This vagueness of criteria make it really hard to make accurate generalizations about AS, every aspie will be different. And severity is going to range from "seems a little eccentric" to "has not set foot outside of the front door in months."
There have to be problems with social stuff, obviously. There have to be habits or patterns of some sort, even if they are just a topic that one regularly obsesses about. And the combination must be perceived as interfering with social, occupational, or other significant aspects of your life.
If you have a hard time coming up with examples of how AS can make life hard (without mentioning too many things which might be uncomfortably close to home), there seem to be plenty of problems discussed here which would do. Whether it's school, work, relationships, or what have you, there are
lots of examples to be found on WP.