I believe in a quote by Fyodor Dostoevsky ......"Man is fond of counting his troubles, but he does not count his joys. If he counted them up as he ought to, he would see that every lot has enough happiness provided for it"
...and I celebrate each and every happiness, achievement, joy...:-)
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"Celebrations" are a blend of Happiness & Rituals.Every person has a right to celebrate in his own manner uninhibited by any taboos or restrictions.You already know when we celebrate we get mad & unbridled sometime as sometimes "Joy knows No Bounds".Man has an inborn instinct of celebrating his belongings & possessions in order to show his inborn vanity.
Most ppl do not celebrate each & every moment of happiness because they are afraid these moments are only temporary but at the same time there are a host of ppl who wait for any happy moment & go mad with joy....they really celebrate.
A number of others celebrate only in order to perform ritual as if this is a binding.Thats NO celebration as it is shorn of real JOY.
A popular song says, " Jio tau is tarah jaisse sab tumara hai..."The most excellant "thing" of joy for us is the most precious gift of God "Our Human frame" !Let us celebrate every moment !