In the first part  of this article we saw how the aesthetic evaluation, as an intelligent activity of beings, whether humans or animals, may have been an implemented feature, or triggered accidentally by playful activities. Whichever way, what is more immediately useful to the artist is to develop that faculty of discernment, in conformant or antagonist manner, in relation to the aesthetic canons established in the different cultures and subcultures.
As we know, some of our sensory organs like those of sight and hearing are designed as captors of particular wave frequency ranges. Of course things can get quite complicated there, so let's stay deliberately away from scientific connotations, rather we are interested in discovering how the information can be processed in our mind, by our brain, not exclusively as external stimuli essential for our survival, but also as source material for our band in the box.
Let's now start exploring the perceptions and see how different connotations can be attributed to them, how a context is first evaluated and what type of information can be associated with them. Let's consider one unique color. Imagine a bright yellow; many of us will make this easy association: yellow = lemon = acid. But then imagine two very different situations:
a) You are walking down the street and you suddenly see a bright yellow flash in the sky.
b) Your computer screen produces a bright yellow flash.
In the first case it's very likely that a considerable level of anxiety will be experienced by many, while in the second case the worst – or best – can happen to anyone is a slight raise of adrenalin.
In the first case a baby will probably cry and a cat will probably run for refuge. The event has a scary connotation; had the flash been pink it would perhaps be less scary. In the second case a baby will probably stare at the screen with its eyes wide open and a cat will probably turn its head at the screen for a quick check. Not really alarming. In no case any spectator will make the anodyne association: yellow = lemon = acid. In both cases, the context is first evaluated.
Although we are simply considering one color, we can easily see the range of reactions, more or less emotional, that it can generate. If that same color is then associated with an object, a small yellow cube for example, while it will probably leave an adult totally indifferent, it might awaken the curiosity of the baby and that of the cat. The baby will probably put it in its mouth to gather more information. The cat might eventually give it a try for signs of animation, one never knows. Were the cube brown, would it attract the same degree of attention from those two? And what if it was gray?
Having seen how a single color can have a different impact on the psyche of living creatures when associated with events or objects, let's go beyond and consider intervals.
As it is pointed out in Katherine Lubar's paper Applying Concepts of Musical Consonance and Dissonance to Color , “Throughout the centuries there have been numerous attempts to correlate elements within the fields of music and visual art [...] applies the principles of consonance and dissonance in musical intervals to their counterparts in color “intervals”. [...] a possible method of analyzing works of art to understand why certain color combinations may work well together.”, a correlation exists indeed, since we are really considering the same phenomena in two different regions of the entire spectrum of waves. The two domains share some common terms as tone, pitch, timbre, color, octaves and more, but not necessarily having equal definitions. A brief incursion into the domain of physics can be useful here. The number of waves that traverse one point in time, measured in cycles (waves) per second is the frequency, expressed in Hertz. The visible range of light is between 430 trillion Hz (red) and 750 trillion Hz (violet). A fundamental sound (root, without harmonics) can have a frequency of say 76 Hz, the audible range being between 12-20 Hz and 20,000 Hz. Waves also have sizes (length) and energy, as well as other properties. There are many distinctions in type and nature from the physicist standpoint between light waves and sound waves, for example the former (optics) are described as electromagnetic transformation of vibratory energy while the latter (acoustics) are described as mechanical – a sound phenomenon cannot take place in vacuum.
Although we do need some degree of awareness of these matters since, as we will see, we must learn how to control intensity as well as other characteristics, we are really interested in what the two domains have in common – all the artistic domains really if we make abstraction of the way and by which means the message is codified, and through which medium or mediums it travels.
In the work cited above we need to be cautious about “[...] to understand why certain color combinations may work well together.”, the assertion is very broad. Many artists have successfully proven over a timespan of at least two centuries that anything goes. In the first article we made a distinction between decorative versus fine arts. In the first category there is indeed a notion of color coordinates, but in a fundamentally creative process total freedom is a prerogative, even though we may decide to only use part of that freedom, or not use it at all. It is then for the artist to decide when and whether he will adhere more or less closely to aesthetic canons. If this weren't true, not only we would never have new canons adopted, but we would never have had any canons at all to follow as educational guidance.
The distance between two frequencies, whether simultaneous or successive, is called an interval, or dyad. A triad is a combination of three frequencies (the minimum requirement to be named a chord).
As a fun exercise we can first imagine two strokes of different colors on a canvas and “hear” the interval, then two simultaneous sounds and “see” the interval. Then do the same with three strokes of different colors and three different sounds. It's important to follow the procedure of the stroke, not just to imagine three colors; your brain will have time to make a self-conscious analysis of the first interval first, then the second, then the chord. A whole world opens up where the number of connections is exponential, of course. The brain of an experienced artist makes those calculations at an incredible speed, because it is trained for this.
While we understand the concept of concordant and discordant, we must remember that those terms were coined centuries ago and that the connotation of disturbing or unpleasant for a discordant interval does not necessarily hold true. As a general rule concordant intervals are considered stable, and discordant intervals unstable. Discordant intervals generate tension and movement, often requiring a resolution. We use tension and release to sustain interest, to break monotony. This is equally true for productions that are static or dynamic in nature, whether at the micro level of the component or at the macro level of the complex compound.
From the artist standpoint, when manipulating colors and sounds we are emitting signals that are meant to be perceived by others. To this respect, the complexity of their arrangement is irrelevant, the exchange takes place in any case, live or deferred, as long as there will be at least one receiver. By manipulating the signals with some degree of complexity the artist intuitively attempts to leave an impression that is capable and susceptible of being recorded in our memory. These impressions may produce emotional experiences, from the very weak or even insignificant to the very strong or even traumatic. These signals are arranged to form a message, or information, ultimately designed to produce imagery that may have more or less of an impact on our emotional, generate feelings, from the indifference through the cool, the pleasant or the anxious.
Supposedly the artist uses this control with discernment. A typical situation: in theater the lighting engineer is responsible for designing the effects which will create a climate corresponding to the dramaturgy of the show, in close collaboration with the director and the scenographer. For this he normally has enough artistic baggage to allow for the communication with those artists. In this show for children that they're putting on, for some of the scenes the director needs to produce some level of surprise, but not to the point of really scaring the children. For this, the lighting engineer will not make an average of the emotional stability in children of age between say 3 and 5 years old, he will have instead to take it from the lower end, too bad if the hard-core will get bored because he cannot afford to make a mistake there. He will then use spots and filters in a way to take the kids somewhere but not too far. He has part of the control over their emotional experience.
Having seen some of the aspects that the visual and the auditive have in common, it's interesting to also note a few radical differences in the expectations of our psyche when dealing with one or the other.
The persistence of light implies the persistence of colors on shapes and volumes in our environment; we deal with this information incessantly, we live with it and our level of tolerance to long exposition is considerable. The duration of sounds instead is variable and generally short; a persisting sound of any nature can quickly cause fatigue or even stress. This characteristic of persisting sounds has even been put to profit by high religious hierarchies through the centuries for its capability to induce certain layers of the populations into that ecstatic state known as trance.
The above is a broad generalization and we must take into account several other factors and parameters that have a decisive incidence on the way the phenomenon is aesthetically evaluated after perception. Intensity for example can radically change an impression from soft to aggressive, from ugly to beautiful.
Because of the day and night pattern the brain of living beings is adapted to this relatively slow rhythm in terms of light. Even with changing light conditions shades vary but hues persist until they dip into darkness. When very high frequencies like those of colors are delivered in packets with relatively fast rhythms they can produce psychedelic effects or stress. To illustrate this imagine the extreme case of a kid playing with a light switch, on and off repeatedly, while you are reading. The exercise can have a very negative effect on your nervous system. Inversely, we seem to accommodate very well with relatively fast rhythms when dealing with sounds, in fact the simple alternating of a same sound with silence can generate a “good feeling”, except perhaps in the case of a pneumatic hammer, although city people may grow to love that sound if it's not too close, as it means the city is working for their comfort. In any case we can sustain the repetition for a certain amount of time, perhaps a few hours. Beyond that, even peaceful or pleasing sounds like that of the breeze through the leaves can cause strain, in spite of its modulation.
We can keep a degree of awareness and possibly identify more or less precisely the wavelength (a color, a pitch) as long as these waves stream in packets of a certain duration. Below 0.08 seconds identification is practically impossible. This is also due to latency and “remnance”, which can also be manipulated artistically. Naturally, in the case of painting the colors are static, but for works of animation, very common on computers and elsewhere, the artist will have to play with rhythm and durations and for this he will get the full measure of their effects on the psyche. Many artists from all disciplines apply these notions intuitively, but a deeper insight generally enhances the level of expressivity and increases the command over the flow of emotive information, that is, information apt to generate emotional response. Film directors and screenplay writers have total command over rhythm, not just music composers or choreographers.
Rests respond to a physiological need. We use rests between individual or small groups of events as an integral part of rhythmic patterns, rests between statements, rests terminating a depiction, a speech, a piece, a movie, and we assign the appropriate length to the rest depending on its function. One important distinction between the visual and the auditive is that, not considering the filtering capabilities which may vary greatly from one individual to another, we can deliberately take a break from the continuous flow of visual information by simply closing the eyelids or turning away towards one other source. We take an active part in the choice of what we want to look at. Instead we cannot easily switch off the reception of sound waves; plugging our ears is not as effective and practical as closing eyelids, it is more attenuation than isolation. In the visual arts, if we make abstraction of lighting compositions, the notion of rest is more subtle and less straightforward, it can be more easily understood for movies, animation movies, computer animations of all kinds and video games. The case of static painting is very special and the notion of rest there is even more subtle. Its consumption is a unique act for which the length is determined by the consumer. In contrast with this, some artists have experimented with live painting.
In all cases the artist needs to understand the notion of rest as an indissociable part of the work, and develop a natural sense for it. As artists we will always check if our work is too busy.
Naturally an artist is first and foremost a technician but a good technician doesn't make an artist. A good knowledge of art history, architecture in particular but also painting, music, helps to get a good insight of the meaning and nature of the creative process. This is true for any discipline and can include programming as well, in that, when it comes to it we can easily see that it is no different from any of the other artistic activities, we have a language, we compose a program, we have interpreters that through some medium will execute the code and output analog signals, and, at the end of the line, spectators who will process these messages, whether actively, interactively or passively. Through the composition we output a discourse.
The creative process is not tributary of the medium through which it is accomplished, not more than the message that it is supposed to carry. Although the medium, tools and techniques are different the process is really one and same thing. So then, we imitate shapes, volumes and sounds of the nature and we like to make new ones, calling upon our senses, not just for survival but for the need to create. But isn't that true survival?