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Question

6. This book discusses all the effort in proving Euclid's Parallel

Postulate was in vain. And concludes with this statement:

"Of course, we say this, we are assuming the consistency

of the venerable Euclidean geometry. Had Saccheri, Legendre, F. Bolyai,

or any of the other dozens of other scholars succeeded in proving

Euclid V from Euclid's other axioms, with the notable

intention of making Euclidean geometry more secure and elegant, they would

have instead completely destroyed 

Euclidean geometry as a

body of thought."

 Explain what is meant by the bold statement.