brings up deaf-blind Helen Keller (shown below) in a related discussion.
Image source: http://www.marxists.org/reference/archive/keller-helen/index.htm
What disabilities arguments really need to show is:
- that computers necessarily lack the ability in question
- that the ability is question is essential either for thought per se or for human-level thought.
To discharge the second obligation would require psychology to specify the nature of thought much as chemistry specifies the nature of water and zoology the nature of tigers. Psychology is still far from up to this.