On one hand, investing to not die of poverty is sensible.

on the other:

Its moral ideal is the worker who takes part of his wages to the savings-bank, and it has even found ready-made a servile art which embodies this pet idea: it has been presented, bathed in sentimentality, on the stage. Thus political economy – despite its worldly and voluptuous appearance – is a true moral science, the most moral of all the sciences. Self-renunciation, the renunciation of life and of all human needs, is its principal thesis. The less you eat, drink and buy books; the less you go to the theatre, the dance hall, the public house; the less you think, love, theorise, sing, paint, fence, etc., the more you save – the greater becomes your treasure which neither moths nor rust will devour – your capital. The less you are, the less you express your own life, the more you have, i.e., the greater is your alienated life, the greater is the store of your estranged being. Everything which the political economist takes from you in life and in humanity, he replaces for you in money and in wealth; and all the things which you cannot do, your money can do

one has to find some happy medium, if one can afford to invest.