Gordon R Dickson 
Chantry Guild [EPUB ebook] 
The Childe Cycle Book 8

Only one thing could lure Hal Mayne away from his research aboard the Final Encyclopedia. It was the shattering news of the Younger Worlds’ oncoming defeat — an inevitable triumph for the cross-cultural hybrids known as the Others. To save Earth’s future in space, Hal must journey to the planet Kultis, where the powerful alternate forces have been mastered by the top secret Chantry Guild. There, Hal Mayne will meet his greatest challenge and ultimate fate — one that will alter mankind’s destiny forever.