In ancient philosophy and astrology what were considered to be the 'climacterics'?

According to the ancient philosophers and their beliefs in astrology, the climacterics were regarded as critical periods in a person’s life.

The belief was thought to have originated with the Chaldeans; a people that existed between the late 10th or early 9th and mid-6th centuries BCE then absorbed and assimilated into Babylonia. Climacterics was also thought to have been influenced by the thinking and teachings of Pythagoras whose philosophy was based on numbers and who imagined an extraordinary virtue in the number 7. According to Aristotle, the Pythagoreans used mathematics for solely mystical reasons, devoid of practical application. The number 7 was also sacred because it was the number of planets, the number of strings on a lyre and because Apollo's birthday was celebrated on the 7th day of each month.

The first climacteric supposedly occurs in the 7th year of a person's life. The rest are multiples of the first, such as 21, 49, 56, and 63. The grand climacteric usually refers to the 63rd year (well beyond life expectancy at birth for most of the ancients), with the dangers here being supposedly more imminent, but it may also refer to the 49th (7 × 7) or the 81st (9 × 9). One can see this notion re-emerging in a fashion in Shakespeare's description of the 7 ages of man (from "As You Like It") and in the observational fascination with the orbital periods of Saturn and Uranus which were thought to hold particular climacteric sway over individual wellbeing.