A difficult thing about autism spectrum disorders is that people expect all these kids to be alike; it's totally possible for each kid to have a different subset of traits. (A "Syndrome," like Asperger's, is a collection of features that often appear clustered together, but a person can have the syndrome without having all the features.)
At age 3 my child appeared to have no empathy, but now he really does seem to. I think for him it may be a learned skill rather than an innate behavior, or else it showed up late, just a part of his social/emotional developmental delay. But that's my kid. Yours will be different, whether or not he has a spectrum disorder.
For me, the difference between "bright and quirky" (which is what we were told many times) and "a disorder" is the extent to which the behaviors negatively affect him and the people around him. He was truly unable to cope with preschool: his inflexibility and difficulty with transitions made it really traumatic for him. For me, this went beyond quirky into "we need help," and the dx was an important starting point toward getting that help.
At 7, after a few years of hard work on his and our parts, he is still bright and quirky, with amazing academic interests, but coping much better with school and the world at large. Pursuing the dx was the best thing we have done for him, because it brought us a team of supports that help him grow toward his potential.
AS tends to shrink a person's world into routine, rigidity, sameness. The therapies have helped us broaden our son's world, which is better for him and for us.
HTH,
DeeDee
