Exegesis
In addition to linking the gankyil with the "wish-fulfilling jewel" (Skt. cintamani), Robert Beer makes the following connections:
The gakyil or 'wheel of joy' is depicted in a similar form to the ancient Chinese yin-yang symbol, but its swirling central hub is usually composed of either three or four sections. The Tibetan term dga' is used to describe all forms of joy, delight, and pleasure, and the term 'khyil means to circle or spin. The wheel of joy is commonly depicted at the central hub of the dharmachakra, where its three or four swirls may represent the Three Jewels and victory over the three poisons, or the Four Noble Truths and the four directions. As a symbol of the Three Jewels it may also appear as the 'triple-eyed' or wish-granting gem of the chakravartin. In the Dzogchen tradition the three swirls of the gakyil primarily symbolize the trinity of the base, path, and fruit. —Robert Beer, The Handbook of Tibetan Buddhist Symbols
The Gankyil as the inner wheel of the Dharmachakra is depicted on the Flag of Sikkim.
The 'victory' referred to above is symbolised by the 'Victory Banner' (Sanskrit: Dhvaja), one of the Himalayan Ashtamangala.
Wallace (2001: p. 77) identifies the ananda-cakra with the heart of the 'cosmic body' of which Mt Meru is the epicentre:
In the center of the summit of Mt Meru, there is the inner lotus (garbha-padma) of the Bhagavan Kalacakra, which has sixteen petals and constitutes the bliss-cakra (ananda-cakra) of the cosmic body.
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