There are some doubting the veracity of the article, and while it is onesided in how it paints Newton, the main conclusion, how Newton's childhood might have contributed to his penchant for isolation is a solid one.

Newton was in his time known as vindictive, secretive, paranoid, sensitive (especially to criticism, he would have made many enemies here on HN) and fairly querulous. Throughout his life he had few friends, wasted no time on idling and had no time for art or music. He was puritanical and deeply religious. In his early notebooks he recorded sins such as: Squirting water on Thy day' and 'Making pies on Sunday night'

He was also prone to rages, as recorded in that same notebook:

'Striking many'; 'Punching my sister'; 'Wishing death and hoping it to some'.

In [1] it is stated: Given the rage that Newton had shown throughout his life when criticised, it is not surprising that he flew into an irrational temper directed against Leibniz and that Newton's assistant Whiston had seen his rage at first hand. He wrote:- 'Newton was of the most fearful, cautious and suspicious temper that I ever knew.'

However, while these aspects of Newton's personality have recently been the topics of focus in various articles and books, what is often omitted is that Newton was only so vindictive if he felt slighted. Granted, this was not hard to do, but there were other aspects to his character[2]:

>He has usually been found to have been an unsmiling and humourless, puritanical man with a countenance that was ‘ordinarily melancholy and thoughtfull’, but which, as Henry More FRS (1614–87) described during a discussion about biblical prophecy, could sometimes become ‘mighty lightsome and chearfull, and in a maner transported.’20

>He always kept Close to his Studyes, very rarely went a visiting, & had as few Visitors, ...excepting 2 or 3 Persons… in whose Company he took much Delight and Pleasure at an Evening...I never knew him take any Recreation or Pastime, either in Riding out to take ye Air, Walking, bowling, or any other Exercise whatever, Thinking all Hours lost, yt was not spent in his Studyes

Newton grew up with what seems to be have been a rather disturbed childhood. Isolated, with indication of having been distant to his mother (at least early on) and mistreated by his stepfather; when coupled with how far ahead he was when compared to his peers†, seems to have resulted in an emotionally stunted, insecure and sensitive individual. Taken together with his obsession with righteousness, it is not hard to see how he might have been difficult to get along with, in turn feeding back to poor social ability and bolstering his inclinations towards being alone.

Newton seemed to have suffered from depression and poor self image throughout his life, exacerbated no doubt, to paranoid delusions later on by consumption of heavy metals as mercury, arsenic and lead.

Certainly Newton was not an easy person to deal with; his brilliance, lack of interests and religiosity coupled with insecurity and pensive nature made for a difficult combination to not somehow run afoul of. He was likely not one to suffer fools lightly and was probably very good at holding a grudge. There are signs that he would have been pedantic and insufferable, the servants at his home certainly had no kind words to lay on him. Yet in the context of his early abandonment, the antagonism of his household against his bookishness, the hostility of his stepfather and the isolated childhood from having grown up with a mind so blazingly sharp, it is difficult to fault him for ending up as one so prone to churlishness. But despite a tendency towards a dour disposition, Stukeley wrote of him in his Memoir:

"according to my own observation, tho'. Sr. Isaac was of a very serious, & compos'd frame of mind yet I have often seen him laugh, & that upon moderate occasions. he had in his disposition, a natural pleasantness of temper, & much good nature, very distant from moroseness, attended neither with gayety nor levity. he usd a good many [shrewd] sayings, bordering on joke, & wit. in company he behavd very agreably; courteous, affable, he was easily made to smile, if not to laugh."

†Stukeley later wrote: one reason why Sr. Isaac did not play much with his schoolfellows, was, that generally, they were not very affectionate toward him. he was commonly too cunning for them in every thing. they were sensible, that he had more ingenuity than they

[1] http://www-history.mcs.st-and.ac.uk/Biographies/Newton.html

[2] http://rsnr.royalsocietypublishing.org/content/62/3/289.full

http://www.newtonproject.sussex.ac.uk/prism.php?id=40