Buy a Brahmavihara - the Four Immeasurables calligraphy wall scroll here!
四無量心 is the cattāri brahmavihārā or catvāri apramāṇāni.
The four immeasurables, or infinite Buddha-states of mind. These four dhyānas include:
1. 慈無量心 boundless kindness, maitrī, or bestowing of joy or happiness.
2. 悲無量心 boundless pity, karuṇā, to save from suffering.
3. 喜無量心 boundless joy, muditā, on seeing others rescued from suffering.
4. 捨無量心 limitless indifference, upekṣā, i.e., rising above these emotions or giving up all things.