Saruman's Motives

[Insidious Rex]

Question to the floor: Just what were Sarumans motives in the Lord of the Rings exactly? It seems he wanted to pursue the ring for himself sometimes and at other times he speaks of working with/for Sauron. Surely Saruman was smart enough to know Sauron would never do this. Or did he really think he would give him a little fiefdom around Orthanc for his own purposes and leave him alone? My thinking is he wanted the ring for himself and didnt want Sauron in the picture at all really which is why he kept it so secret at first but then he held off attacking Sauron when Sauron was at Dol Guldur which makes you think well maybe he wanted to ally with him. But then of course he does attack him and is the main reason they drove him out. So whats the deal. Was it just all about getting a hold of the ring and being The Man or was it about some kind of evil alliance? He was after all doing Saurons bidding by making an army and keeping the men occupied in Rohan so Saurons forces would have less opposition to face.