The safest way of not being very miserable is not to expect to be very happy. - Arthur Schopenhauer

Change alone is eternal, perpetual, immortal.

All striving comes from lack, from a dissatisfaction with one's condition, and is thus suffering as long as it is not satisfied; but no satisfaction is lasting; instead, it is only the beginning of a new striving. We see striving everywhere inhibited in many ways, struggling everywhere; and thus always suffering; there is no final goal of striving, and therefore no bounds or end to suffering.

Science is not a taxi-cab that we can get in and out of whenever we like.