Sensation & Intuition

Sensing & Intuition are the Perceiving Processes, and when combined with an Attitude, constitute the Perceiving Functions.
Those who prefer Sensing are called Sensors.
Those who prefer Intuition are called Intuitives.

Essence

In order to understand Sensing and Intuition, we must first consider what the human mind does (though I think all cognitive animals do this!) when it's trying to understand the world.

First, the human mind receives sensations. Sights, sounds, smells, tastes, touches (pressure sense on the skin). In addition, it receives pleasure & pain from various sources. The term one can use for both of these is qualia.

From here on, 'sensations' will be used to refer to both sensations like sight and hearing, as well as pleasure and pain.
When we speak of 'empirical evidence', we are speaking of some way of demonstrating how some idea corresponds to an experience that can be had.

As this occurs, the mind then seeks to comprehend patterns in these qualia, which are then used to infer and predict things that are apart from the given sensation. In other words, in discerning these patterns, it discerns the meaning of experiences.

Sensing involves a bias toward sensation. One who has an inclination toward Sensing prefers to collect and think upon what can be directly experienced.
Intuition involves a bias toward meanings. One who has an inclination toward Intuition prefers to collect and think upon what can be inferred from things, and how one can do so.

Vices and Virtues

The Vice of Sensing is that it can tend to be small-minded, or even closed-minded; to take interest only in what they can personally experience, or even to outright reject anything that does not bear directly upon the personal life of the Sensor.
The Virtue of Sensing is that it is hard to deceive, at least about the things it deals with personally. It is usually quite in touch with the things it deals with on a day to day basis.

The Vice of Intuition is that it's often too willing to consider that for which it has no or too little evidence; to miss what is right in front of it, too busy thinking about what it might mean. What meanings it infers may easily drift from the evidence they actually possess. People whose 'heads are in the clouds' are usually Intuitives.
The Virtue of Intuition is its ability to look deeper into reality; to see the meaning beneath things, and not be deceived by simple appearances. These meanings are also the scientific, philosophical, or other kinds of understanding that we have today, and that have created the modern world - including the Internet and this blog!

Traits

Tend to prefer local, personal action, i.e. They tend to wish to directly witness the evidence of the benefit of their actions, and so they tend to both act on the immediate environment, and do it themselves. An example is my ISFJ mother - she is personally involved in doing good around our local neighbourhood, such as going out and delivering leaflets to doors advertising a meet up group for lonely elderly people. Intuitives tend not to this as much, not minding others doing the work and preferring a larger impact.

Tend to be involved in ideas. Ideas are in line with meanings because ideas are the meaning of events. For instance, E = mc^2 is an idea that was derived from various experiments, such as the way light bends around large celestial objects. Where a sensor may be more interested in the precise facts and events recorded (the trajectory of the light), intuitives are more interested in what those results imply - in this case, prove (the equation, E = mc^2).

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