Well maybe, but he never seemed to have thought so:
The idea that Crowley believed Aiwass and Lam to be the same entity, or that either were extraterrestrials from Sirius, is only the speculation of Kenneth Grant and those who have based their research on source material written by Grant. Additionally, very little can be said about the inspiration for the Lam portrait or what Aleister Crowley thought about it. [...]
At least to the present author, this description of a kingly, tall, dark man in his thirties does not fit the Lam drawing. More importantly in relation to the subject of this post, the description does not match up at all with that of a “grey alien,” which many people relate to Lam.
The next important piece of information to take from Crowley’s depiction of Aiwass is that he never actually saw Aiwass at all. He only heard the voice of Aiwass from over his left shoulder, and from the furthest corner of the room. Not once did he actually look at Aiwass. His physical descriptions are only impressions.
So here we have a character description based only on non-visual impressions, and which doesn’t seem to correspond with the pictured Lam or grey aliens at all. This is the only known written description of Aiwass by Aleister Crowley.
Crowley himself never wrote much of anything at all about Lam, where the figure came from, or his ideas/thoughts about the subject in the drawing. What he did write was limited to a short, two sentence commentary in The Voice Of The Silence, which will be discussed later in this article.
Full Story: Blasted Tower: misconceptions about aleister crowley, lam, aiwass and alien contact
See also: A Media History of Gray Aliens
This illustration of HG Wells’ tale of human evolution, “The Man of the Year Million,” is one of the oldest depictions of the “big headed genius” trope:
The concept is based on Lamarckian evolution, specifically the idea that body parts we use frequently will grow larger but parts we use less frequently will atrophy. Wells took this to the logical extreme, postulating (with tongue in cheek) that we would eventually grow gigantic brains and hands but tiny legs and torsos.