I have written at length?

Does "I have written at length" mean "I have written at careful details"?

Context:

In The Understanding of the Brain (1973), Eccles summarizes his philosophy: "Now before discussing brain function in detail I will at the beginning give an account of my philosophical position on the so-called 'brain-mind problem' so that you will be able to relate the experimental evidence to this philosophical position. I have written at length on this philosophy in my book Facing Reality. In Fig. 6-1 you will be able to see that I fully accept the recent philosophical achievements of http://en.wikipedia.org/wiki/Karl_Popper with his concept of three worlds. I was a dualist, now I am a trialist! Cartesian dualism has become unfashionable with many people. They embrace monism in order to escape the enigma of brain-mind interaction with its perplexing problems. But Sir Karl Popper and I are interactionists, and what is more, trialist interactionists! The three worlds are very easily defined. I believe that in the classification of Fig. 6-1 there is nothing left out. It takes care of everything that is in existence and in our experience. All can be classified in one or other of the categories enumerated under Worlds 1, 2 and 3.