Constitution is defined as the structure, composition, physical make up or nature of something, comprising inherited qualities modified by the environment. 
Temperament means a peculiar or distinguishing mental or physical character determined by relative proportion of humors according to the medieval physiology. It means characteristic or habitual inclination or mode of emotional response. 

There are basically four temperaments
— NERVOUS , BILIOUS, SANGUINOUS and PHLEGMATIC. 

Nervous - indicates constitutions of quick actions and high strung.
Bilious - have a tendency to liver diseases.
Sanguinous — related to congestive and plethoric states
Phlegmatic — sluggish in reaction.
Combinations of these primary types in different proportions give rise to many other types of temperaments.
 
GENETIC FACTORS       INTRA-UTER1NE ENVIRONMENT
                   C/C MIASM
                                                      EXTRA-UTERINE ENVIRONMENT
 CONSTITUTION 

Physical make-up of the individual illumines manifold aspects of personality and many of the behavioral patterns.
Physical characteristics are linked closely to the genetic set-up and this suggests that the physical and psychic characters are intimately related. So also the term constitution emphasise physical structure as well as the biological function.

CLASSIFICATION OF CONSTITUTION

CHINESE CONCEPT - YANG & YIN
AYURVEDIC CONCEPT - VATHA - PITHA - KAPHA
HIPPOCRATIC CONCEPT — Hippocrat classified constitution into 2 types — short and thick & long and thin. According to him e first type is prone to apoplectic conditions and the second type is prone to tubercular affection.

                                                      Short & Thick
PHYSICAL APPEARANCE
                                                     LONG AND THIN
                                                    SANGUINE

HUMOURS           CHOLERIC
                                 PHLEGMATIC
                                 MELANCHOLIC
 
BAZIN — classified constitution into 3 types - SCROFULOUS, GOUTY & SYPHILLITIC
                                                                                                CARBONIC CONSTITUTION
 
VANNIER’S & ZISSUS          PHOSPHORIC CONSTITUTION
                                                            FLUORIC CONSTITUTION 

The characteristics of carbonic constitution are mentally and physically upright persons, having square white regular teeth, slight acute angle between Ibre-arm and upper-arm, orderly, undemonstrative, responsible and capable. They are Psoric. Cal carb, kali carb, mag carb, nat carb, graph, carbo veg, carbo anim are the drugs having this constitution. 

Phosphoric constitution have scroflilous or tubercular diathesis. Tall , thin delicate, easily tired persons with long yellow teeth but well fitted. Arm forms perfect straight line when stretched. Dislike hardwork but orderly and thstideous. Usually Psychotic. Calc phos, phos acid, kali phos, phos, mag phos are the main drugs.

Flouric constitution is characterized by unbalanced irregular body formation with obtuse angle of outstretched arm, teeth irregular and ill fitted, untidy, cunning and unreliable. Capable of heroism, sanctity and wickedness.
Predisposed to diseases of nervous system, dislocation of the joints and suicide. Mainly Syphillitic. Flouric acid, calc flous are the main drugs.
 
                                              HYDROGENOID
VON GRAUVOGL     OXYGENOID
                                             CARBO-NITROGENOID
 
Hydrogenoid constitution is characterized by the excess of water in the body. They are aggravated by moisture and humidity, prone to dropsy and anasarca, and suffers from tissue growth of benign type. They belong to the Sycotic group. Ars, dulc, nat suiph, nitr acid phytolacca, rhustox, thuja, dig etc are the main drugs.

Oxygenoid constitution is characterized by the accumulation of excess of oxygen with resultant destruction of tissues. Body is thin and thus ill on change of season. Destructive, disorders involving the genitalia and diseases of central nervous system. Body is prone to ulcerations and self— destruction. Generally of syphillitic background. CaIc phos, ferr phos, nat phos, phos, phos acid, iod, sit, calc, natr mur, hell, tuberc, syph, merc sol, are the main drugs.

Carbo — Nitrogenoid constitution is characterized by excess of carbon and nitrogen and suffers from functional disorders of body and mind, marked by erratic working of the heart, lungs, kidneys, liver, spleen etc. they are mainly Psoric. Ars, ars iod, calc phos, crbo veg, hep, iod, kali bich, lach, lyco, natr mur, sulph, zinc met, etc. are the main drugs. 
 
                                                                        ASTHENIC
ERNST KRETSCHNER (1921)      ATHLETIC
                                                                        DYSPLASTIC
                                                                        PYKNIC

  By taking a limited number of physical characteristics Kretschner classified constitution into asthenic,athletic and pyknic — with an additional one — dysplastic.

Asthenic refers to frail, linear physique. A defeciency in thickness combined with an average unlessened length. Lean narrow built with a skin poor in secretion, narrow shoulders, muscles, delicately bones limbs, narrow flat chest, sharp rib angle, and thin stomach.

Athletic constitution is characterized by strong development of the skeleton, musculature and skin, a middle sized man with projecting shoulders, superb chest, firm stomach and trunk tapers in its lower edge so that the pelvis and the magnificient leg seem almost graceful compared with the size of the upper limb and particularly hypertrophied shoulder.

Pyknic refers to plump physique.