A common Credit Card Machine
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Many things can cue a person to act a certain way, be it what someone remarks to another concerning the intelligence level of their mother, or perhaps if a certain scent beckons a hungry traveler to sneak into the nearby kitchen to see if that pie over there has cooled enough to spare a slice.  The impulse of actions, as well as the urge to do those actions, are brought on by input through the five senses - touch, sight, hearing, smell, and taste.  Color, for instance, brings on more impulses than we ourselves wish to admit.  For example, the credit card machine to the left.  Out of all the buttons on the device, the red button catches the eye first, and begs to be pressed (Manor).  

Sight, however, affects behavior on such a subtle level that barely anyone notices it.  Picture, if you will, a credit card machine - specifically, the ones found at the end of checkout stands in grocery stores and supermarkets.  Notice the buttons - the red button sticks out the most, crying out to be pressed.  Even though it will result in the effect that you do not want (providing that there isn't an error in checkout), the fact remains that you did want to push it at some point (Manor).  Thus, colors affect our behavior, whether we want it to or not.

 

Within the Middle Ages, were people affected by the colors of various coat-of-arms?  Below is a table comparing the colors to their heraldic meaning, the meaning in Color Psychology as according to infoplease.com and Society's Stereotypical view.  The Stereotypical View data was compiled through via a small questionnaire that merely asked participants what they thought of when they immediately see each color.


Color Heraldry Meaning Color Psychology's Meaning Society's Stereotypical View
MetalsGold (Yellow) Wealthy, Generous Cheerful, Optimistic Caution, Happy, Warm
Silver (White)Peaceful, Pure Innocence, Purity "Holy," Cold, Pure
Main ColorsBlackGrief, Secretive Authority, Power Mourning, Darkness
BlueTruthful, Loyal Cold, Depressing, Loyalty, Masculine, Peaceful, Tranquil Calm, Cheerful
GreenHope, Joy (Wade), Wise Calm, Fertility, Nature, Wealth Lucky, Wealth
PurpleRoyal, Dignified Feminine, Romance, Royalty, Luxury, Sophistication, Wealth  Royal, Mysterious
RedMilitary fortitude (Wade), Passionate Energizes, Alert Stop, Hurry
Stains
(appears very rarely)
MulberryUnpredictable Genuineness, Sad, Wistful Soothing, Sleepy
Dark Blood-RedNot hasty in battle, and yet a victor (Wade), Blood-thirsty N/A Blood, Danger
Tawny orangeWorthy ambition (Wade), Meek N/A Fiery, Hot


According to Wikipedia.com's entry on color psychology, there is both positive and negative connotations with each color.  The following table consists of the colors in heraldry, the assumed meaning in heraldry, and the negative and positive associations with each according to Wikipedia.com.  These associations are based on connections to things in the Western Culture (Color Theory - Wikipedia.com).

 

Color  Heraldry  Meaning     Positive  Associations     Negative Associations  
MetalsGold (Yellow) Wealthy, Generous Sunlight, joy, happiness, optimism, idealism, wealth, summer, hope Cowardice, illness (quarantine), hazards, dishonesty, avarice
Silver (White)Peaceful, Pure Reverence, purity, snow, peace, innocence, cleanliness, simplicity, security, humility, marriage, sterility Coldness, sterility, clinical, surrender, cowardice, fearfulness,  
Main ColorsBlackGrief, Secretive  Power, sophistication, formality, elegance, wealth, mystery, style Evil, death, fear, anonymity, anger, sadness, remorse, mourning, unhappiness, mystery
BlueTruthful, Loyal Seas, skies, stability, peace, unity, harmony, tranquility, calmness, coolness, confidence, water, loyalty, conservatism, dependability, cleanliness, technology Depression, coldness, obscenity, technology
GreenHope, Joy (Wade), Wise  Nature, spring, fertility, youth, environment, wealth, money , good luck, vigor, generosity, go, grass Inexperience, envy, misfortune, jealousy, money, illness, greed
PurpleRoyal, Dignified  Elegance, sensuality, spirituality, creativity, wealth, royalty, nobility, ceremony, mystery, wisdom, enlightenment Cruelty, arrogance, mourning, profanity, exaggeration, confusion
RedMilitary fortitude (Wade), Passionate  Passion, strength, energy, fire, love, sex, excitement, speed, heat, leadership, masculinity, power Danger, fire, blood, war, anger, revolution, radicalism, aggression, stop
Stains
(appears very rarely)
MulberryUnpredictable N/A N/A
Dark Blood-Red Not hasty in battle, and yet a victor (Wade), Blood-thirsty N/A N/A
Tawny orangeWorthy ambition (Wade), Meek  Energy, balance, heat, fire, enthusiasm, flamboyance, playfulness Warning, danger, fire


These tables reveal that the heraldic meanings of the past still hold true to colors today, give or take.  As to if the color of the coat of arms affects the bearer, it is uncertain as coats of arms were passed down from generation to generation (Slater).