Human society in general and each individual in particular have developed a certain system of evaluation and attitudes which has an expression in each language. Apart from spontaneous speech based on the productivity of language forms and models [14], there are ready-made  forms, for example, idioms which  are more evaluative, emotional and expressive than descriptive vocabulary.

    Expressing  evaluation and emotional attitude of a person to the world around them and on themselves is one of the basic functions of an idiom, thus evaluation  (or value component)  occupies a special place in the structure of phraseological meaning. Traditionally, the phraseological meaning is represented as a unity of three components: denotative, significative and connotative.

     The nature of value component in the structure of phraseological meaning is understood ambiguously.  Most often, value component is considered as connotative, expressing a certain attitude to the denotation. This point of view is held by A. V. Kunin, I. V. Arnold, Yu. A. Gvozdarev and others.

1. I. Shakhovskiy [11] considers value component as a part of denotation since the features reflected by the value semes are inherent in the designated object. Value component contains information about the value of what is displayed in the denotation of the idiom. This value is spotted by the subject of evaluation on the basis of social evaluation scale, norms and stereotypes.
2. N. Telia believes that rational evaluation in idioms refers to the denotative aspect of meaning – to what is designated as objective in the real world [13], and emotional evaluation should be attributed to understanding the features of the object from the real world  in the ideal world , and therefore emotional evaluation  refers to the connotative area.

     According to N. F. Alefirenko, evaluation is often contained in the phraseological signification (for example, Russian idiom lizat’ pjatki (lit. lick the heels) is  evaluated disapprovingly, whereas  an idiom probivat’ sebe dorogu (lit. make your way) is an approving one). Emphasizing the fact that in this regard, the phraseological signification is more abstracted from the denotation, revealing the connection with the connotative element of an idiom, the author concludes that in contrast to the lexical meaning, connotation usually prevails in the semantic structure of phraseological units [1].

      Thus, value component of  phraseological meaning  implies ability  to express a positive or negative attitude of the subject to a non-linguistic object [8].

      In its function, language evaluation is opposed to pure nomination. In this respect, idioms are divided into two classes: non-evaluative and evaluative. All those whose nominative function consists in identifying the properties of the denoted object are considered non-evaluative idioms. In the meaning of these idioms there is no judgment about the value of the denoted object, since the object itself does not qualify but describes something  from the real world  [13]. The following colour idioms are non-evaluative: zheltyje stranitsy (lit.yellow pages), belyje stikhi (lit. white poems), belyj tanets (lit. white dance), white dwarf, red cross, etc.

     Since idioms are units of indirect nomination, their connotative meaning is of particular importance. In the structure of connotation, there are two evaluative macro components: objective evaluative (rational), which is current semantic competence of native speakers; it’s an element of the associative verbal network, since it is closely related to the cognitive picture of the world and emotive evaluative (emotional), indicating the emotional relation of the subject to the designated reality. As the psychic basis of connotation is association, we considered it possible to divide the bulk of colour idioms in the Russian and English languages into several semantic groups according to various kinds of associations which form their value meanings [10], thereby adding evidence to the theory that evaluation is a component of the connotative phraseological meaning.

     We have identified three groups of Russian and English colour idioms (the total sample is 217 Russian and 324 English colour idioms) according to various factors responsible for evaluation: 1) idioms based on  physiological or psychological influence on the subject of  evaluation (general physiological or psychological associations ) (this group is 19.6% of the total sample in Russian and 20.2% in English);  2)  idioms  based on universal external associative effect on the subject of evaluation (this group is 39, 3% of the total sample in the Russian language and 46.5 % in English) and 3)  idioms grounded on the factor of cultural, historical and symbolic impact on the subject of evaluation (this group is 41.1% of the total sample in the Russian language and 33.3% in English).

     When  spotting the  value type in the meaning of an idiom,  we rely on the following main criteria proposed  by E. F. Arsentyeva [2]:

• criterion of lexical components  — the value seme of the idiom lexical component implies the value seme of the whole idiom. For example, videt’ vse v chernom tsvete ( lit.to see everything in black) has a negative rating since the component «black» has a negative seme «joyless, gloomy, pessimistic»;
• semantic criterion — the semantics of the prototype (i.e., the meaning of non-idiomatic phrase or expression, to which the prototype goes back) is the main source of the idiom value meaning. English idiom to lay out a red carpet contains a positive seme «to give a solemn reception»;
• 3) extra linguistic criterion – idiom value meaning is determined by such extra linguistic phenomena as customs, traditions, superstitions, legends, myths, etc. For example, Russian expression  da gori ono vse sinim plamenem! (let it all burn in blue flame!) means that the person has lost the last hope to arrange any business properly and has  given up on it  (it has been noticed that at night in swamps  or near fresh graves it is possible to see burning lights which are products of combustion of methane. The belief connects the appearance of blue lights with the ordeal of restless souls: sinners who died without repentance, suicides and people who just drowned in the swamp).

      Language evaluation which is determined by the properties of an object of non-linguistic reality and reflected in the human mind and fixed in the meaning of a language sign expresses itself in the functioning of the language form, in the dictionary definition, in the dictionary comment or in the dictionary value labels [7]. Thus, dictionary labels could be the criterion for allocating value component in the phraseological meaning. Negative evaluation is expressed in the dictionaries by  these labels: derog., impol., iron., taboo, vulg. etc.;  positive evaluation : approval., laudatory. Moreover, value marks contained in lexicographical meaning of an idiom could also constitute value spotting criterion (axiologically marked adjectives that express a positive or negative value – good, kind, pleasant, greedy, coarse, aggressive). For example, prinimat’ chernoje za beloje ( lit. to take black for white) −  to take bad for good, dat’ zelenuju ulitsu ( lit. to give a green street) − to create particularly favorable conditions for the free promotion of someone/something,  or for the implementation of something, to see red  − to become very angry, white elephant − an unwanted or useless item.

     Phraseological meaning can contain  negative (pejorative), positive (meliorative) or neutral value components.

     Pejorative component is an indicator of a negative attitude to the object of evaluation, expressing disapproval, condemnation, or censure of any properties or qualities of the object.

     In the opinion of such linguists as A. Wierzbicka, E. M. Wolf, A. V. Kunin, Yu. A. Gvozdarev, A. D. Reichstein, O. P. Ermakova, G. N. Sklyarevskaya, in the lexical structure of any language negatively connotated units dominate. According to G. N. Sklyarevskaya’s observations, almost 80 % of the language metaphor has  pejorative nature [12].

1. D. Reichstein explains this asymmetry of the phraseological system as a more acute and differentiated emotional and speech-making reaction of people to negative phenomena, as well as a tendency to use ready-made speech forms, including fixed expressions, in stressful, negative emotional states [9].

     After analyzing value meaning of phraseological units with the basic color terms white, black, red, blue («sinij» and» goluboj» in Russian), green, yellow in the Russian and English languages (the total sample is more than 650 idioms) [10], we found out that there is indeed an asymmetry towards a negative evaluation. Thus, in English phraseology, pejorative evaluation is most typical for white colour idioms (only 4 obvious areas of positive evaluation were spotted («favorite, happy, lucky», «clean, unspotted», «innocent, morally clean», «decent, well-bred»), while 9 areas were evaluated negatively («rage, anger», «fear, cowardice», «flattery», «illness», «undesirable, useless», «having a minimum cost», «hypocritical», «slavery, prostitution», «negative attitude of people of colour to the white race»), black (12 areas of negative evaluation were identified («anger, aggression», «depression, sadness, pessimism», «sick, unhealthy», «beaten, bruised», «dirty», «condemned, out of favor, morally dirty», «illegal, dishonest», «evil, insidious, devil», «notoriety, bad reputation», «slander, blacken», «failure», «negative attitude to members of the black race») and 3 areas of positive («profitable, solvent», «desirable, successful», «fashionable, popular»), blue (there were 5 obvious areas of negative evaluation («dull, depressive», «rude, obscene», «intoxicated», «puritan», «unknown, unexpected») and 3 positive («loyalty, constancy», «unusual, rare», «honest, reliable»), red (11 identified areas of pejorative evaluation («aggression, anger», «drunkenness, carousing», «unrestrained, hot», «embarrassment, shame», «prostitution, passion, vice», «arson, fire», «negative attitude to the Indians of North America», «bloody», «communist», «unprofitable, in debt», «danger, prohibition, anxiety») and only 2 positively evaluated areas («beauty, health, vitality» and «solemn, festive, special»), yellow (6 negative areas («cowardice», «low, despicable, treacherous», «low quality», «unhealthy, sick», » negative attitude to people of Asian origin», «danger, warning») and 3 positive ratings («greeting», «striving for the desired», » gold, gold coins»),  whereas in Russian, the largest number of units with pejorative meaning is found in  black colour idioms (8 areas of negative evaluation («bad mood, melancholy, pessimism», «physically hard, rude, common», «plain, not ceremonial», «household, dirty, low quality», «death, trouble», unlucky, unsuccessful», «evil spirit, devil», «dishonest, malicious, criminal») and none positive), yellow ( 6 areas of negative evaluation («treason, betrayal, cowardice», «disease, danger», «sadness, melancholy», «low quality», «negative attitude to people of Asian origin», «gold, money») and 1 positive («sunny»).  The analysis of value semantics of colour terms like ‘sinij’ and ‘goluboj’ in Russian  yields the following results. The peculiarity of Russian is in its differentiation of lexemes denoting the hue of blue: «sinij» and «goluboj».  The negative evaluation of «sinij» by Russians  is lexically expressed through the seme weakening of positive value meaning of this colour term  (only the idiom sinjaja ptitza (lit. a blue bird) is evaluated positively; the rest of a few Russian idioms with «sinij»-component are negatively evaluated). Originally positive evaluations of «goluboj» in the Russian language are expressed in the meaning «idyllic, innocent, related to dreams»; while a negative evaluation of this colour term has developed through association with the homosexual subculture.

      Meliorative component manifests itself in positive evaluation of the object,  expressing approval or encouragement. The analysis showed that green remains  positively evaluated color in both Russian and English phraseology. Supposing that the area «greenery, plants» is neutral, we can say that in both languages there are an equal number of areas of positive and negative  evaluation (in Russian, positive areas of  evaluation are: «aimed at nature protection», «horticultural, agricultural», «permission, freedom», negative — «inexperienced, naive», «drunkenness, alcohol», «unhealthy, painful, dreary». In English, the positive areas are: «full of energy, vigorous, healthy», «permission, freedom», «environmental, aimed at nature protection», negative — «inexperienced, young, naive», «jealousy, envy», «associated with marijuana»). The phraseology of the Russian language is also characterized by  positive evaluation of white (7 positive  areas («beautiful, aesthetically pleasing», «opposite to the dark realm of the dead», «innocent, immaculate», «pure, unblemished», «best, highest quality», «without bad or malicious intentions», «privileged, qualified» against 3 negative («weakling, incompetent», «negative emotional or physical state», «unknown, otherworldly») and red (8 areas of positive  evaluation («beautiful», «elegant, fashionable», «best, top quality», «ceremonial, festive, honorable», «pleasant, correct», «eloquence», «rich,  abundant», «important, significant») and 5 negative («prohibition, danger», «fire, arson», «bloody», «communist», «preferred by fools»).

      When value approval or disapproval is not expressed clearly in the meaning of an idiom, it is called neutral value component of phraseological meaning (e. g. belyje nochi (lit. white nights) − summer nights typical of some northern regions when the evening twilight directly passes into the morning without the onset of darkness, belyj tanets (lit.white dance) − a dance which ladies invite gentlemen to, out of the blue − suddenly, unexpectedly.

      The group of idioms with neutral value component also includes phraseological units where the combination of positive and negative meaning gives a neutral result. For example, white lie − harmless (minor) untruth (positive and negative value components are combined (on the one hand, a lie is a negative and condemned phenomenon, on the other, «white lie» is not telling the truth in order to spare someone’s feelings, not to upset someone). Considering this idiom   from the position   of rational evaluation and highlighting the useful/harmful, favorable/unfavorable nature of the concept (utilitarian evaluation) or morality/immorality (ethical evaluation), we can say that this idiom tends to the positive part of the scale.

     Value component in the structure of phraseological meaning can be expressed either explicitly or implicitly. Value is expressed explicitly if at least one of the components of an idiom or its internal form has evaluative nature. If all components of an idiom are non-evaluative and its internal form is blurred, then value is expressed implicitly [7].

     The formation of  colour idioms with explicit evaluation is based on metaphorical concepts that are interpreted and structured in terms of other concepts (color in   indirect meaning) (chernyj knjaz’ (lit. black prince) – the head of a terrorist organization, chernyj pozhar ( lit. black fire) – soil erosion,  seryj cardinal (lit. grey cardinal) – a political figure exerting powers behind the scene, without drawing attention to themselves, to feel blue – to feel depressed or melancholy, green pea − a person who is inexperienced, black look − threatening look) and conventional (symbolic) knowledge, i.e. general knowledge about a concept that people of a particular cultural group share –  concept of color, for example (color as a symbol) (zelenaja ulitsa (lit. green street) – a free path without obstacles and delays, usually for the movement of railway and motor transport, krasnyj den’ kalendarja  (lit. red calendar day) – festive day, significant day,  true-blue — of loyalty or patriotism (esp. of a conservative),  to give someone a green light – to give someone a permission, better red than dead – expression used during the Cold War by some people opposed to nuclear weapons, meaning that it would be better to be controlled by a Communist government than to be killed in a nuclear war). Color components of these expressions  have evaluative nature and carry information presented in the meaning of the idioms.

     Implicit evaluation in phraseological semantics is associated with unmotivated meaning of an idiom, the influence of extra linguistic factors, and evaluation of  internal form of an idiom (clear or blurred). For example, the idiom  to be (remain) in the black  and its variations move into (return to, get to, etc.) the black (to be profitable, not to have debts) are formed on the basis of a non-metaphorical concept, the word black  originally meant the color of ink, which traditionally was used to record clients who did not have debts in financial documents. This extra linguistic information has been transformed over time into the metaphorical meaning of the  black colour term in these idioms, which have come to mean «to be profitable, solvent», and the direct color meaning of the word «black» has stopped to be recognized by native speakers.  The model of formation of these idioms is the following: » the object coloured black  + extra linguistic information, which is the basis of metaphorical redefining process  → distinguishing feature of the subject» Positive implicit evaluation is related to the  assessment of this situation in society:   it is good when you don’t have debts.

     To sum up, the evaluation of colour idioms, identified on the basis of various criteria, can have  positive, negative and neutral character and be expressed either explicitly or implicitly. The idea of asymmetry of the phraseological system towards pejorative evaluation is supported by an overwhelming number of colour idioms with a negative  value component in the Russian and English languages. Expressed in an idiom, value  attitude to a particular color by Russian and English speakers   indicates differences in the language picture of the world of the two languages.

      Value component of color idioms can be considered as a connotative element, since the evaluation in a large number of such phraseological units is formed under the influence of the observed features of objects, cultural and historical facts, emotional and sensory perception that causes positive or negative reactions and associations.