I realise now that the good lady who taught us [at the kindergarten] had had an orthodox Froebel training, and was at that time amazingly up-to-date. I can still remember almost all the lessons in detail, but I think what thrilled me most was the discovery that yellow and blue paints made green.
Source: The Autobiography of Bertrand Russell, v.1
More info.: https://russell-j.com/beginner/AB11-220.HTM
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