I vaguely recall a description about manifestations of the truths offered by a system being pseudo-proofs for that system to be right, in a context in which logical certainty is not possible. Consider the following examples:
A theory (e.g. "those who open doors with the left hand are less prone to falling to the ground"), which cannot be definitely proven, but can't be proven wrong either, is propounded, even if absurd. Manifestations of the predictions of the theory would not be real proofs, but could still convince.
It is not possible to clearly know whether Physics are right. The creations of technology, based on the knowledge it provides, work, so Physics seem right -- although such intuition cannot be proven.
For what it is worth, I remember this conviction taking place where the success of someone would convince others to follow him or her. However, I do not know if it was a thought of myself or if I read it somewhere. I have tried searching, and also looked the Wikipedia pages about fallacies, but have not found it. If such pseudo-argument is recognized, how is it named?