In approaching circumstantial evidence provided by epidemiology in support of the lipid hypothesis of atherogenesis, basic precepts include accuracy in terminology and in defining the end point to be measured. Cause must be used as the sole prerequisite without which the disease does not occur. Risk factors are not causes unless proven by other means and coronary heart disease (CHD) is an inappropriate monitor of the severity of atherosclerosis. Misuse of cause, risk factor and CHD had lead to the multifactorial concept of the etiology of atherosclerosis.