Mrs Parker was evidently a gentle, amiable, sweet-tempered woman, the properest wife in the world for a man of strong understanding but not of capacity to supply the cooler reflection which her own husband sometimes needed; and so entirely waiting to be guided on every occasion that weather he was risking his fortune or spraining his ankle, she remained equally useless.
Jane Austen wrote with a hugely ironic tone about the position and role of women in society and especially of the qualities that were seen to make them "good" wives. Mrs Parker has many of these qualities in abundance; she is sweet-natured, not a nag, indulgent of her husband's ideas and obsessions and an effective cheer squad behind him. When he is working towards an informed decision or goal, this is a very good thing, but when he is carried away with excitement and enthusiasm for a project and needs a calming reflective influence, she is not it. She does not possess the ability to think particularly well or to look at actions and consequences, and so she is absolutely no use in reigning in her sometimes maverick husband.
He held it indeed as certain that no pserson could be really in a state of secure and permanent health without spending at least six weeks by the Sea every year.
Mr Parker loves Sanditon but he loves even more the idea of the Sanditon of the future that he has been developing in his head for a couple of years. He is a great believer in sending people to the seaside for convalescence, something which the medical profession seemed to believe in two, as many of Victorian England's seaside towns were filled with "convalescent homes". He took this theory one step further and maintained that not only was the seaside good for physical health, but also for mental and emotional health as well.
In part this was a complete conviction that he genuinely held, but it was also intertwined with his own belief that there was money in the benefits of sea air and the seaside. He wanted to encourage tourism within the town, and so the idea that is should be of huge benefit to the body and mind was extremely important in his quest to make Sanditon the primary seaside resort in the south.
Those who tell their own story, you know, must be listened to with caution.
This is an extremely astute observation, because every first person story is always told with the rose-colored tinge of the teller. Beyond the accuracy question, there is also a belief amongst the gentry that to talk about oneself when this talk is unsolicited is extremely low class, and indicates a total lack of awareness about what is proper and what is not. This is seen to be the most important thing in English society in this novel, and also throughout Austen's works.
