I looked into the quote from Pascal. It turns out to be from his "Pensées" (Thoughts). In the original French, the passage in question reads:
> Quand je m'y suis mis quelquefois à considérer les diverses agitations des hommes, et les périls, et les peines où ils s'exposent dans la Cour, dans la guerre d'où naissent tant de querelles, de passions, d'entreprises hardies et souvent mauvaises, etc., j'ai dit souvent que tout le malheur des hommes vient d'une seule chose, qui est de ne savoir pas demeurer en repos dans une chambre.
> When I have occasionally set myself to consider the different distractions of men, the pains and perils to which they expose themselves at court or in war, whence arise so many quarrels, passions, bold and often bad ventures, etc., I have discovered that all the unhappiness of men arises from one single fact, that they cannot stay quietly in their own chamber.
I think I would translate that last bit as "... I have often said that all the unhappiness of men derives from just one thing: not knowing how to sit still in a room."
It's a lot more subtle than that.
| "de ne savoir pas demeurer en repos dans une chambre."
Is literally: "To not know how to remain at rest in a room"
There is certainly no mention of one's own room, but it is a conclusion one could draw from the previous paragraph: these issues would certainly be avoided if one did not leave their house, but without additional context, it's not the only conclusion.
From the given context, my interpretation is closer to its literal core: people cannot content themselves to be still, in a state of calm.
People routinely and actively flee moments of calm, moments of idle. Glance around public transport, and you'll see people cramming every second with something - the ageless inability to remain calm in a room.
> Quand je m'y suis mis quelquefois à considérer les diverses agitations des hommes, et les périls, et les peines où ils s'exposent dans la Cour, dans la guerre d'où naissent tant de querelles, de passions, d'entreprises hardies et souvent mauvaises, etc., j'ai dit souvent que tout le malheur des hommes vient d'une seule chose, qui est de ne savoir pas demeurer en repos dans une chambre.
One English translation (http://oregonstate.edu/instruct/phl302/texts/pascal/pensees-...) renders this as follows:
> When I have occasionally set myself to consider the different distractions of men, the pains and perils to which they expose themselves at court or in war, whence arise so many quarrels, passions, bold and often bad ventures, etc., I have discovered that all the unhappiness of men arises from one single fact, that they cannot stay quietly in their own chamber.
I think I would translate that last bit as "... I have often said that all the unhappiness of men derives from just one thing: not knowing how to sit still in a room."