In this thesis, the condition of autism spectrum (AS) is reviewed with regard to cognitive theory and re-evaluation of the current literature. The experiences of individuals, with and without a diagnosis of AS, will be compared and contrasted. The levels of evidence for each cognitive theory of AS will be explored. These cognitive theories are: Theory of Mind (ToM); Weak Central Coherence theory (WCC); Executive Functioning Theory (EF) and Enhanced Perceptual Functioning Theory (EPF). It is argued in this thesis, via a process of falsification (for example, all swans are white is proven to be false when we find a black swan) that AS is a particular cognitive difference associated with the use of single attention. Whereas typical individuals have a brain configuration allowing the use of divided attention and associated connectivity with the sensory system allowing a diverse interest system, autistic individuals use single attention with less connectivity to a sensory system leading to less related multiple interests.