Richard Feynman’s Notes for Self-Education

Jillian Hess | Noted | Apr 13 2026

For Feynman, not-knowing was an exciting state.

This is my biggest takeaway: We should fear certainty more than doubt. Learning to live with uncertainty is an essential aspect of learning, as Feynman said in 1981:

You see, one thing is, I can live with doubt and uncertainty and not knowing. I think it’s much more interesting to live not knowing than to have answers which might be wrong.

Rocket Science for Monkeys

Francis Gooding | London Review of Books | Apr 23 2026

Infants and children learn iconic words earlier and more easily than they learn arbitrary words, and iconic words remain dominant in the vocabulary of children until around the age of six, after which there is a gradual shift towards arbitrary words. ‘Iconic words are easier to learn,’ Mithen writes, because ‘their meaning is grounded in the sensations experienced by the child – the sound, size, shape, texture, movement and other properties of the object or action being named.’ By providing a fundamental link between speech sounds and objects in the world, they ‘scaffold the entire process of language acquisition’.

Perceiving a link between a vocalisation and the tactile or visual characteristics of an object is thought to be dependent on ‘cross-modal perception’, the tendency for multiple senses to interact while perceiving something. The most familiar form of this is synaesthesia, whereby sense perceptions of one kind also stimulate parts of the brain used in perceptions of a different kind; one may experience a strong association between a word or sound and a particular colour or shape. It is thought that synaesthesia and other cross-modal phenomena take place because of ‘leakage’ between different parts of the brain, which is common in younger children: before the age of about ten, the developing brain is still so plastic and richly interconnected that there is typically a lot of traffic between regions that later become more distinct.

In 2001, two cognitive scientists, V.S. Ramachandran and Ed Hubbard, published a paper proposing that synaesthetic links between vocalisation, bodily movement and the sense perception of objects could have prompted the creation of iconic sounds in an early human ancestor, thus opening the gateway to speech. They returned to maluma and takete, to the ‘small’ sound of ‘i’, and to other cases in which the movement of the mouth seemed to mimic the meaning of a word, or even the movement of other parts of the body: for instance, when the mouth or lips appear to borrow from the typical action of the hand, as in the numerous words for ‘you’ that involve the ‘pointing’ of the lips towards another person; or the way in which the making of the small i or ee sound could correspond to the pincer action of forefinger and thumb when picking up something small. If synaesthetic links were operating in the increasingly flexible brains of early hominins, perhaps they could have had an effect on vocalisations, resulting in the creation of the first mutually intelligible words – mutually intelligible because their meanings would have been established through shared experience.