Independent Institute scholars have criticized the Patient Protection and Affordable Care Act on economic, legal, ethical, and privacy grounds. Senior Fellow John C. Goodman has argued that the ACA's architects could not have foreseen all of its negative consequences because healthcare is a complex system. For this reason he claimed the ACA exemplifies what Nobel laureate economist F. A. Hayek called “the fatal conceit.” Independent Institute scholars were critical of the pre-ACA system as well for problems they attributed to government policies that promoted third-party payment systems and removed market pricing from healthcare delivery. Goodman has proposed reforms replacing the ACA, most notably the adoption of a fixed-sum, refundable tax credit for the purchase of health insurance, a credit equal to the cost of new enrollees in Medicaid. Other major proposals include converting all medical savings accounts into Roth-style Health Savings Accounts that feature after-tax deposits and tax-free withdrawals; allowing anyone to buy into or exit from Medicaid; and denationalizing and deregulating health insurance exchanges but requiring exchanges to offer health-status insurance.