The King's English

Kingsley Amis

Perceive, perception
To perceive something, or that something is so, used to mean simply to take in with the senses or the mind; you would perceive a tree on the horizon or the importance of heredity. The word is almost a synonym for see, except that a degree of effort or special ability is implied. But whatever you perceived was understood to be really there.
Then, in the earlier 1970s, a new meaning started creeping in. From then on what was perceived no longer had to be really there, it might be just the way you saw it, looked at it, saw not in the primary meaning of taking in reality but in the secondary meaning of taking a view of, e.g. I see things differently now. Nowadays journalists write of X's perception of the Labour Party when X might see the Labour Party as anything from a capitalist conspiracy to a gang of communists, while Y's perception might be entirely different and yet equally 'valid'.
When Samuel Johnson said to an acquaintance, 'Sir, I perceive you are a vile Whig,' he certainly did not mean to say anything as wishy-washy as that his uneven and temporary view of the chap took him to be some sort of vile Whig; he meant he now knew the other chap was a depraved supporter of parliament rather than the crown, etc. As Johnson would have known, the Latin roots of perceive indicate that it meant to grasp thoroughly. Latin roots of English words are notoriously often bad guides to meaning, but not seldom, as here, they may remind the user of what the English word once unequivocally meant.
This user of perceive and perception will remain at best potential until further notice. The distinction between their traditional and contemporary meanings is quite substantial enough to deter me from ever running the risk of being thus misunderstood. Such is a common result of verbal innovation: instead of anything valuable, it causes either muddle or the departure of a once-useful word.

 The moral of The King's English: Words are dangerous.