Question

"I could feel " What could be the anguish?

Answer 1

Hint: Firdaus Kanga is the author of A Visit to Cambridge. He was a writer who had travelled extensively around the world. He is a writer, journalist and actor. In this, the authors discuss how, regardless of one's disabilities, one should keep their attention on the positive and their abilities.

Complete answer:
A Visit to Cambridge is an illustration from a travelogue that shows the exchange of opinions between two exceptional people on what it meant to be "differently-abled." This chapter is a brief tour of Cambridge, England, which was both fun and moving experience for the author. He met Stephen Hawking, a brilliant yet paralysed astrophysicist, and spoke to him for a full half-hour at a time.
Prof. Hawking's mind was filled with brilliant ideas, but he couldn't express them clearly and aggressively. It must be like wishing to fly only to discover that your wings have been clipped.

The frustration (anguish) was that he couldn't find the right words to express himself on his screen/computer. He was angry. He couldn't express himself openly, despite the fact that ideas were racing through his head.
Or
His anguish could stem from his inability to articulate so many things that remain unspoken in his mind due to his disability. Having to rely on a machine to express himself is, in part, unbearable.

Note: The chapter – A Visit to Cambridge – emphasises to students that physical disability can not be seen as a barrier to reaching greater heights in life. Rather than concentrating on the physical impairment, one should learn to overcome the mental disability.