It is still acceptable to conduct psychological experiments on uninformed participants; everyone in the world does it every day. It is only &quot;unacceptable&quot; if you call yourself a psychologist while you&#x27;re doing it, and subsequently try to publish a paper about it in one of the standard journals of the field.<p>Just by way of example, I saw a very funny TV show in which the setup was this: someone dressed up in a beekeeping suit walked through a public park with a stack of white boxes, stumbled, dropped them, and started sprinting in the other direction. The show did this several times and aired the footage.<p>It turns out that people in a public park are likely to run after the seemingly-panicked guy in bee armor when he runs away from a pile of boxes he just dropped. If you wrote a paper about this after doing it rather than showing your footage on TV, it would be totally unexceptional as a psych experiment. But writing the paper doesn&#x27;t make the experiment any more or less dangerous to the unwitting subjects. It&#x27;s just the trigger for institutional review.<p>The review system exists because professional researchers today generally are not self-funding. This isn&#x27;t a problem for science fair entrants.