I believe that the 18th century concept of sensibility came to artistic fruition with the Aestheticist movement.​ Sensibility seems to be a peculiarly British phenomenon. Its primary characteristic is a marked sense of responsibility. 

There is something significant about sensibility being quintessentially British. I propose that sensibility is one facet of imagination. Something seems to have sparked in the mind of Enlightenment England that would change the nature of humanity, guiding it from base competitiveness to altruism.

This tectonic shift in the consciousness of man has not come without its drawbacks. The current bleeding-heart, hyper-apologetic, politically correct, champagne-socialist, dominant countercultural meme is the curdled grandchild of sensibility.

But all is not lost if we can identify the original impetus contained in the push towards Aestheticism. Why? Because Beauty matters. ​From Wikipedia:

George Cheyne and other medical writers wrote of "The English Malady," Cheyne considered this malady [sensibility] to be the result of over-taxed nerves. At the same time, theorists asserted that individuals who had ultra-sensitive nerves would have keener senses, and thus be more aware of beauty and moral truth. Thus, while it was considered a physical and/or emotional fragility, sensibility was also widely perceived as a virtue.

I will state that it is the objective of Pulchrism to ​identify Beauty without succumbing to histrionic sentimentality. Balance is beauty, and apology is insult. Sensibility is a gift and a burden. It's time to remember and accept that beauty can have a definition, and that it is not blasphemous to attempt to define it. The Oxford English Dictionary defines beauty as follows:

1 Such combined perfection of form and charm of colouring as affords keen pleasure to the sense of sight: a.I.1.a in the human face or figure.

2 That quality or combination of qualities which affords keen pleasure to other senses (e.g. that of hearing), or which charms the intellectual or moral faculties, through inherent grace, or fitness to a desired end​.

3 The prevailing fashion or standard of the beautiful.

4 The abstract quality (esp. in sense 1) personified.

​We can carry on forward, but we've got to exercise discernment in matters of conscience. No more can we abide mediocrity and ugliness in the name of Tolerance.

More information on Whistler's Peacock Room can be found here.