The use of the title ""Holy One of Israel"" appears equally in both ""halves"" of the book of Isaiah. This unifying element argues for Isaiah's authorship of the whole book.

The answer is: True.

Explanation:

Isaiah sole author of his book. Isaiah's book can easily be divided into two parts.

The main reason why critics declare that Isaiah's work is the work of at least two writers is because they believe that a prophet could not see beyond the horizon of his own time.

Despite the questions he has suffered, the traditional attribution of the entire work to the prophet Isaiah is supported by various verifiable sources.

On the other hand, there are compelling reasons to maintain that the book of Isaiah is the work of a single writer. One of them is the constant use of certain expressions.

The answer is: True.