91av

Continuing Conor Feehly's interesting points in his article "What makes a mind?", I would propose that "agency" isn't an adequate definition of "self". As Feehly points out, the concept of agency is complicated because comprehensive, inanimate systems can make complex decisions based on novel input. But we don't attribute agency to neural network software programs. …

The comment in your Leader that "The sleep industry, for one, could reorientate itself around helping people... understand that they are getting more and better sleep than they realise" seems naive: why would an industry that monetises our worries about poor sleep try to reassure us in this way? The closing paragraph of another article …

Isabel Woodford's article on postnatal depression (PND) in fathers struck a chord with me. When my children were born in the early 1980s, PND wasn't recognised as a paternal issue. I don't recall feeling depressed myself, merely always tired, yet I was expected back at work the next day. Today, fathers are far more involved …

Regarding your article about overcoming tiredness, after a distressing life event in 1995, my GP asked me if I needed sleeping tablets. I replied that I was getting very little sleep, but I had read an article in 91av that said that students were found to do equally well in exams if they had …

Just one or two bad nights' rest can increase our reaction times (28 February, p 30)

As a retired paint chemist, I enjoyed the article "A study in scarlet". However, I cannot understand why the review of blue pigments excluded phthalocyanine blue, which was first marketed as Monastral Blue in 1935. Phthalocyanine blue became a major source for blue colourations in the house paint, automotive ink and plastic industries. I personally …

Regarding Chris Simms's article "The secret to living a meaningful life", there is a meaning to life, and that is: to enjoy every moment to the best of our ability. Animals, in my experience, are happiest when their basic needs are met. For a cow, this may mean a full belly and a shady tree …

I found the article concerning the evolution of human chins very interesting. The suggestion that sexual selection could be partially or wholly responsible implies that this evolutionary trend could take place quite rapidly. I would be interested to know whether the researchers, or anybody else, have noticed another human oddity: increasing neck length ( 21 …

I have often wondered whether the shape of the human jaw is influenced by speech as well as diet. For example, people who use the precise consonants required by certain languages seem to have distinct lips. The use of the jaw to pronounce the "r" of American speech seems to give the jaw more projection. …

The term "moral Machiavellis" is used by some to describe people who use "dark tetrad" traits for good (7 March, p 24)