Once wife so brushed the head Archimedes by a rag for spilling water in the bathroom that he finally understood why this is so!
Somehow in the garden an apple so hit hard Newton on the head that he immediately understood - why!
Once Faraday's servant dropped a heavy magnet on his foot so successfully that he understood that without motion, current, like pain, does not form.
Mendeleev have suddenly got a headache like that from too strong moonshine that he realized that vodka should only be forty-degree.
Pushkin gathered his strength and before his death looked at Lermontov in such a way that the latter understood - he was he who should develop the cause of Russian poetry further.
Dostoevsky only realized before the failed execution what crime and punishment are, and who is really an idiot.