My cat is scared of my chair.?

I just got a new chair for my computer, Its the kind that spins.He's terrified of the chair!How can you make a cat stop being scared of a chair?

I'm guessing he(?) saw it spin and maybe thought of it as something predatory. What I'd do is hold your cat closely in your arms, talking in soft tones and petting him/her then walk slowly to the chair, sit down with your cat still in your arms and just hold him for awhile, then let the chair slowly turn back and forth and just keep talking to him, holding him. After awhile he/she will be more curious than scared; then soon after that he/she will be leaving hair all over your chair and you will have to move him/her to use your computer (like I do!) lol. Truly!