[Consultant32452]

Manipulation in American English generally has a negative connotation. Technically you can say your doctor manipulated you into losing weight because of your heart disease, but that would be an odd usage. You would normally say she persuaded or convinced you. Conversely, the car salesman manipulated you into buying the unnecessary extra warranty.

American Heritage dictionary has this definition for manipulation:

>Shrewd or devious management, especially for one's own advantage.

Lastly, if you try to convince me of something "just to see if you can" that would definitely be perceived as negative to most people. You did it for your benefit, the enjoyment or education of doing it.