[excuse-me]

If you were an active practioner in the field you wouldn't need a patent, you would have trade secrets.

Suppose I'm a consultancy and i invent an improvement to an MRI machine. I can sell the idea an MRI maker - or without patent protection I would have to set up in business making million $ MRI machines and compete with Toshiba/Philips/GE etc in order to benefit from my small improvement.